Article: 227133 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Radial attenuation Date: Tue, 25 Jul 2006 09:16:30 -0700 Message-ID: References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> On Tue, 25 Jul 2006 12:22:38 +0100, "Reg Edwards" wrote: >and Richard Clark would again unjustly accuse me of trolling. ;o) Hi Reggie, Do those nails in your palms really 'urt that much? 73's Richard Clark, KB7QHC (rolling dice at the bottom of Reggie's posts) Article: 227134 of rec.radio.amateur.antenna Message-ID: <44C645A4.46D82830@shaw.ca> From: Irv Finkleman Subject: Re: Capacitors for HF Antenna References: <1153727139.482229.205720@s13g2000cwa.googlegroups.com> Date: Tue, 25 Jul 2006 16:23:40 GMT palaniappan chellappan wrote: > > Cecil Moore wrote: > > Bill Turner wrote: > > > You didn't give many details such as the bandwidth of the antenna, but > > > if you use the NP0 type ceramic capacitors you should be ok. Loops, > > > especially small ones, are notorious for narrow bandwidth and stable > > > caps are a must. > > > > I once used disc ceramic bypass caps to try to tune an > > antenna. They went up in flames. For a small loop, I > > would at least use doorknob quality caps. > > Thanks to all for replies, > Actually my requirement is to pump 4W into 1meter diameter loop > antenna. > I need to tune the antenna to resonance 13.56Mhz and then match it. > I using some fixed capacitors and variable capacitors of small range > for fine tuning. > Now i am using ceramic fixed and ceramic variable capacitors and found > that its performance is good (I am not sure, the problem may in my > transceiver also). > > I thinking of trying other capacitors, how about following combinations > mica fixed + mica variable > mica fixed + air variable > > Is it worth to buy mica capacitors ? > can i simply buy mica capacitors ? , i found some vendors selling rf > mica capacitors , > is there any big difference between them for HF frequency ? > > regards, > palani Try a short length of RG-8 or similar. Cut it longer than necessary and then prune it to length. Irv VE6BP -------------------------------------- Visit my HomePage at http://members.shaw.ca/finkirv/index.html Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm -------------------- Irv Finkleman, Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP Calgary, Alberta, Canada Article: 227135 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Date: 25 Jul 2006 09:31:14 -0700 Message-ID: <1153845074.694631.112920@b28g2000cwb.googlegroups.com> References: <29GdnQxiI6gLuSTZnZ2dnUVZ_t-dnZ2d@comcast.com> David G. Nagel wrote: > Al Klein wrote: > > On Mon, 24 Jul 2006 23:37:53 -0400, "clfe" > > wrote: > > > > > >>ago or better. How did the rep act like a snob? He turned to his bud who was > >>with him behind the table and ignored others "trying" to gain his attention > >>and talk to him about whatever. Oh - he may look and say Hi, but god forbid > >>you interrupt his conversation with his buddy. So much for the "MEET YOUR > >>ARRL REP HERE" > > > > > > Instead of canceling your membership you should have complained to > > Newington. I've known a lot of League reps - some are great, some are > > so-so and some are terrible. About the same mix as any large group of > > human beings. Canceling your membership didn't make the situation any > > better. > > > Remember also that most reps are elected by the few who bother to vote > for them. Most are unopposed. Sort of like politicians. > > Dave WD9BDZ anyone that thinks you jion the ARRL and stand for office should inquire of Carl Stevenson Article: 227136 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: Radial attenuation Message-ID: References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> Date: Tue, 25 Jul 2006 12:32:49 -0400 On Tue, 25 Jul 2006 12:22:38 +0100, "Reg Edwards" wrote: >Cecil, > >There has been a temporary improvement in my Alzeimer's affliction. > >The attenuation along a radial is given by = > >Attenuation = ( R / Ro + G * Ro ) / 2 nepers. > >Where - > >R = HF Conductor resistance. >G = Shunt leakance or conductance, related to soil conductivity. >Ro = Resistive component of line impedance Zo. > >One neper = 8.686 dB. > >If I published the source code you would be asking even more questions >and Richard Clark would again unjustly accuse me of trolling. ;o) >---- >Reg. > Hi Reg, I believe your temporary Alzhiemers affliction began some time ago, when you repeatedly reminded me that BLE forgot to indicate the ground conditions. Even though the conditions are irrelevant when sufficient radials effect a near-perfect ground, you either skimmed BLE too quickly, or the Alzhiemers effect had already taken place. I'm going to quote from two BLE pages below: "Fig 7 earth conductivity = 0.2 x 10^-4 mhos/cm^3 Fig 8 earth conductivity = 1.0 x 10^-4 mhos/cm^3 Fig 9 earth conductivity = 0.2 x 10^-4 mhos/cm^3 Fig 10 earth conductivity =1.0 x 10^-4 mhos/cm^3" "Fig 18 shows the distribution of earth loss for G = 22 degrees, and G = 88 degrees, for 15 and 113 radial wires, when the frequency was 3000 kilocycles and the earth conductivity is 0.2 x 10^-4 mhos per cm^3." It's true they didn't mention permittivity, but at least they did recognize conductivity, and reported it. On the other hand, concerning the difference in results between using BLE or Radials3, unless I missed the critical point somewhere along the way, perhaps the difference has been misunderstood, where Radials 3 shows usefulness drops off more quickly with distance from the radiator than BLE. As I understand it, when only a few radials are present, the longer length is unnecessary. I now quote again from BLE: "Fig. 6 shows the actual current in the earth for the same conditions. These diagrams show that the ground system consisting of only 15 radial wires need not be more than 0.1 wavelength long, while the system consisting of 113 radials is still effective out to 0.5 wavelength." Does this not agree with Reg's Radials3? If not, please tell me what I'm missing. (I do not have Radials3, and am only commenting from what I've read in the various posts.) Walt, W2DU Article: 227137 of rec.radio.amateur.antenna From: "H. Adam Stevens, NQ5H" Subject: Re: You're not a real ham if you never took or passed a Code test. Date: Tue, 25 Jul 2006 11:36:06 -0500 Message-ID: <12cci3kou98rq35@corp.supernews.com> References: <44C6294C.C57BD5EC@mred.com> In 1964 I passed the 13 WPM test on the first try at the Dallas FCC office. I was 14. There are plenty who can top that, I'm sure. The rulemakers "stabbed themselves in the back with their own ballpoints" (To quote an article from Electronics World in 1962.) when they created CB. But, as said article went on to point out, the industry needed a shot in the arm. That article has stuck in my head to this day. This isn't about creating the best operators, it's about selling the most junk and having the most votes. 73 H. NQ5H Article: 227138 of rec.radio.amateur.antenna From: "H. Adam Stevens, NQ5H" Subject: Re: Is It double bazooka less noisy? Date: Tue, 25 Jul 2006 11:37:55 -0500 Message-ID: <12cci71i2kp027d@corp.supernews.com> References: <1153105845.609970.257280@h48g2000cwc.googlegroups.com> <1153137324.594379.153720@i42g2000cwa.googlegroups.com> <12bnmv728399a54@corp.supernews.com> <1153343561.889811.229020@s13g2000cwa.googlegroups.com> <12btggnfvuof911@corp.supernews.com> <8VLvg.10483$2v.1274@newssvr25.news.prodigy.net> <1153433788.383801.90830@75g2000cwc.googlegroups.com> <1153445174.176522.120710@75g2000cwc.googlegroups.com> <12c27qui0r4ohb8@corp.supernews.com> <3e9xg.11685$2v.4048@newssvr25.news.prodigy.net> <1153828704.177146.42840@m73g2000cwd.googlegroups.com> This is hilarious. No matter in what context, it appears bazookas cause long threads. 73 H., NQ5H Article: 227139 of rec.radio.amateur.antenna From: ricknj10@hotmail.com (Rick) Subject: Re: Rotor Cable? Message-ID: <44c6478f.14504875@news.optonline.net> References: Date: Tue, 25 Jul 2006 16:41:15 GMT Buy 300 feet of regular cable. The kind made for 100 foot runs. Do a quick check on the kitchen table. Measure the voltage at the motor, note the voltage drop in the cable. Rig up a transformer in series with the line to the rotor such that it kicks up the voltage. I did this successfully a while back. Yes it takes a little effort but works perfectly. As I remember I kicked up the 24 volts on a CDE rotor to about 30. The other wires in the cable are used for detecting the position of the rotor and can tolerate the long run. The other thing you can do if you have enough scrap romex or other copper wire is to parallel it with the rotor cable. Not necessary to have enough to go the entire 300 feet. For example, if you have enough of say #12 romex cable to go from the shack to the base of the tower, use it to parrallel the rotor cable and make your measurements. Use your head, experiment. It is just ohms law we are dealing with here, not rocket science. Good luck. Rick K2XT Article: 227140 of rec.radio.amateur.antenna From: "Richard Fry" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> Subject: Re: Radial attenuation Date: Tue, 25 Jul 2006 12:03:13 -0500 Message-ID: <44c64e05_2@newsfeed.slurp.net> "Walter Maxwell" wrote > ... I now quote again from BLE: > "Fig. 6 shows the actual current in the earth for the same conditions. > These > diagrams show that the ground system consisting of only 15 radial wires > need not > be more than 0.1 wavelength long, while the system consisting of 113 > radials is > still effective out to 0.5 wavelength." > > Does this not agree with Reg's Radials3? If not, please tell me what I'm > missing. (I do not have Radials3, and am only commenting from what I've > read in > the various posts.) ___________ Possibly not. Here is a paste of one the early responses to the first thread started by Reg on this subject , which shows that with radials_3, radiation efficiency doesn't just stop improving with longer radials, it can also get worse. QUOTE Reg, a bit confused by these results from RADIAL_3 96 radials, 7MHz, antenna height 10.72m. Soil 500ohm*m, permittivity 13\ Radials and antenna 1.024mm (18AWG), radials 3mm deep(surface) Radial Length, %Efficiency 2m, 93.19% 3m, 93.83% 4m, 92.47% 5m, 86.01% 6m, 80.39% 7m, 85.92% 8m, 89.06% 9m, 89.59% 10m, 88.22% 11m, 85.99% 12m, 85.51% 13m, 86.67% ?? Dan END QUOTE /RF Article: 227141 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Cutting cable length to match 1/4 wave 162 MHz antenna? Date: Tue, 25 Jul 2006 10:02:31 -0700 Message-ID: <9chcc29p0isct558rn4vvq2sdhnrh1uv70@4ax.com> References: <59ywg.3365$bP5.367@newsread1.news.pas.earthlink.net> On Tue, 25 Jul 2006 15:38:04 +0200, Helmut Wabnig <...._.--_.-_-..._-._.._--.@.-_---_-._*_.-_-> wrote: >Does anybody know the input impedance of his receivers in use? Hi Helmut, Stand-alone receivers may differ, but in transceivers, the receive path, up to a point, is identical to the transmit path. As such, a 50 Ohm design is universal. Now, if there is any divergence from that value, you must expect that signal power is being reflected away from the detector. Certainly, any high Z active amplifier may be used, but in an untuned front end, this is hardly a virtue. Stand-alone receivers, like the R-390, can have higher Z inputs with tuned front ends. The R-390 includes what is called an antenna trimmer to further optimize the input. It also has two distinct antenna inputs, balanced and unbalanced. >How would you measure the input impedance? This takes a special signal generator with a known output Z. You simply place a series variable resistor in line, and watch the receiver's signal meter as you vary the resistance until half the voltage is observed. The input Z is the sum of the signal generator's output Z and the variable resistor's value. Take warning that a variable resistor's value is going to be the next difficult thing to determine. It is not simply a matter of measuring its value (or rotational angle) with a VOM. However, absolute accuracy is rarely needed in this regard and a VOM reading will be suitably close. 73's Richard Clark, KB7QHC Article: 227142 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Is It double bazooka less noisy? References: <1153105845.609970.257280@h48g2000cwc.googlegroups.com> <12bnmv728399a54@corp.supernews.com> <1153343561.889811.229020@s13g2000cwa.googlegroups.com> <12btggnfvuof911@corp.supernews.com> <8VLvg.10483$2v.1274@newssvr25.news.prodigy.net> <1153433788.383801.90830@75g2000cwc.googlegroups.com> <1153445174.176522.120710@75g2000cwc.googlegroups.com> <12c27qui0r4ohb8@corp.supernews.com> <3e9xg.11685$2v.4048@newssvr25.news.prodigy.net> <1153828704.177146.42840@m73g2000cwd.googlegroups.com> <12cci71i2kp027d@corp.supernews.com> Message-ID: Date: Tue, 25 Jul 2006 17:10:02 GMT H. Adam Stevens, NQ5H wrote: > This is hilarious. > No matter in what context, it appears bazookas cause long threads. I don't remember the bazooka ever being discussed before in the context of precipitation static so it is essentially a brand new topic. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227143 of rec.radio.amateur.antenna From: "RHF" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 25 Jul 2006 10:12:17 -0700 Message-ID: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> References: Slow Code wrote: > That's what you have to decide. > > SC SC - 10-4 Good Buddy ! :o) ~ RHF I give Honor and Respect to any Amateur Radio {Ham} Operator : Who has built and uses his own Receiver and CW Transmitter for regular CW use. I will gladly read their posts and listen to their arguments as to "Why" CW is important to the ARS. - BUT - "IF" all they have every done is bought ready-made equipment and claim that CW is necessary to the ARS - please don't waste my time. . . . . Article: 227144 of rec.radio.amateur.antenna From: "H. Adam Stevens, NQ5H" Subject: Re: Is It double bazooka less noisy? Date: Tue, 25 Jul 2006 12:44:02 -0500 Message-ID: <12ccm30e6qt3e67@corp.supernews.com> References: <1153105845.609970.257280@h48g2000cwc.googlegroups.com> <1153343561.889811.229020@s13g2000cwa.googlegroups.com> <12btggnfvuof911@corp.supernews.com> <8VLvg.10483$2v.1274@newssvr25.news.prodigy.net> <1153433788.383801.90830@75g2000cwc.googlegroups.com> <1153445174.176522.120710@75g2000cwc.googlegroups.com> <12c27qui0r4ohb8@corp.supernews.com> <3e9xg.11685$2v.4048@newssvr25.news.prodigy.net> <1153828704.177146.42840@m73g2000cwd.googlegroups.com> <12cci71i2kp027d@corp.supernews.com> Actually, I recall your mentioning it before, Cecil. But I'll be damned if I'll go search threads from near half a decade ago to prove it. Brand new topic or not, it involves bazookas. Cheers H. NQ5H "Cecil Moore" wrote in message news:Kfsxg.137782$H71.54135@newssvr13.news.prodigy.com... > H. Adam Stevens, NQ5H wrote: >> This is hilarious. >> No matter in what context, it appears bazookas cause long threads. > > I don't remember the bazooka ever being discussed before > in the context of precipitation static so it is essentially > a brand new topic. > -- > 73, Cecil http://www.qsl.net/w5dxp Article: 227145 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Choices, Choices, Choices... CW or CB? Date: Tue, 25 Jul 2006 11:10:52 -0700 Message-ID: References: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> ORIGINAL MESSAGE: On 25 Jul 2006 10:12:17 -0700, "RHF" wrote: >I give Honor and Respect to any Amateur Radio {Ham} Operator : >Who has built and uses his own Receiver and CW Transmitter >for regular CW use. I will gladly read their posts and listen to >their arguments as to "Why" CW is important to the ARS. >- BUT - "IF" all they have every done is bought ready-made >equipment and claim that CW is necessary to the ARS >- please don't waste my time. ------------ REPLY SEPARATOR ------------ Construction/design skills and operating skills are two different things. What does one have to do with the other? Did you build your own car? Dishwasher? Toaster? Razor? Bill, W6WRT Article: 227146 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Cutting cable length to match 1/4 wave 162 MHz antenna? Date: Tue, 25 Jul 2006 11:12:44 -0700 Message-ID: References: <59ywg.3365$bP5.367@newsread1.news.pas.earthlink.net> ORIGINAL MESSAGE: On Tue, 25 Jul 2006 15:38:04 +0200, Helmut Wabnig <...._.--_.-_-..._-._.._--.@.-_---_-._*_.-_-> wrote: >Side note: >Did you note I left out the receiver? >Does anybody know the input impedance of his receivers in use? >How would you measure the input impedance? ------------ REPLY SEPARATOR ------------ I would think a MFJ SWR analyzer would do it. Haven't tried it, but can't think of a reason why it wouldn't work. Bill, W6WRT Article: 227147 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Radial attenuation Date: Tue, 25 Jul 2006 11:11:28 -0700 Message-ID: References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> On Tue, 25 Jul 2006 12:32:49 -0400, Walter Maxwell wrote: > you either skimmed BLE too quickly, or the Alzhiemers >effect had already taken place. Hi Walt, Reggie's only defense against plagiarism (a charge he loves to bandy about) is claiming to have NOT read BLE. It mimics his railing against software users as intellectual cripples when he has a trove of software offered like dope to school children on the playground. Reggie, It is amazing how you can spit in the faces of those commending you for your software; and you do it with full vigor and glee. You may want to ponder your legacy as a maker of crutches (un-referenced executables) or leaving a testimony in open source code. Even with these positive examples you sneer at your source to gain the rhetorical advantage, and yes, that makes you a troll (and this is decidedly different from what the Brit's call eccentrics, or what we call characters). The one complaint I've heard frequently from you when you are asked to write something comprehensive (there are models in history from Heavysides that you similarly dismiss) is that there is not enough time. You seem to have plenty enough time to anticipate my banter, or to otherwise respond to/with trivialities. This has got to be the height of decadence. 73's Richard Clark, KB7QHC Article: 227148 of rec.radio.amateur.antenna Date: Tue, 25 Jul 2006 14:26:07 -0400 From: jawod Subject: Re: QST's Louisiana Loop References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> <44c4bbd9_1@news.iprimus.com.au> <44c63c89_1@news.iprimus.com.au> Message-ID: <9db61$44c66290$453d9423$19131@FUSE.NET> Maxwell Smart #99 wrote: > jawod wrote: > >> test wrote: >> >>> jawod wrote: >>> >>>> I am considering building the Louisiana loop shown in this month's >>>> QST. It is basically an inverted delta loop. I don't know if I can >>>> model it on EZNEC (I guess I can...but I've only progressed through >>>> a dipole or two). >>>> >>>> I actually intend to string it up among some trees in the backyard >>>> in a sort of temporary fashion. >>>> >>>> Realizing the directionality involved, I will aim it toward Asia >>>> over Alaska. >>>> >>>> Now, any caveats or recommendations or ? before I embark on my first >>>> antenna build? >>>> >>>> I don't at present even know the feedpoint impedance but I intend to >>>> use RG8U for feedline if that's possible. There is no mention of an >>>> UNUN or Balun in the article. >>>> >>>> What do youse think? Thinks? >>>> >>>> John >>>> AB8WH >>>> >>>> PS, I'll give the hoberman sphere a rest for a while (hi) >>> >>> >>> This antenna was meant to be fed as a multiband antenna using open >>> wire feedline and a tuner. >>> >>> Its height dependent. The takeoff angle on 20 is high. I myself would >>> use a dipole with open wire feedline. However the authors intentions >>> was for a compact multiband antenna. If you have trees use the large >>> loop as in the ARRL antenna handbook. >>> >>> For a better antenna that feeds with open wire line and that has a >>> ideal low angle pattern on all band from 20 meters to 10. Look at the >>> horizontal magnetic slot antenna. You can find details in the latest >>> RSGB handbook. >>> >>> A good tuner for these antennas is the Balanced Tuner by Measures. >>> >>> >>> Pat >> >> Pat, >> Thanks for the input. >> I have a question. >> >> Why do you say that the antenna was meant to be fed using open wire >> feedline? >> >> In the article, it shows an SO239 bulkhead to be attached to RG8U cable. >> >> John >> AB8WH > > I Hope we talking about the same antenna? > > I am talking about the antenna in this months QST page 38 ZS6AAA > > "The Compact Quad Multiband Hf Antenna" August 2006 > > So i hope i have not crossed wires here. But this antenna is open wire > fed, supported on a single fibreglass pole. > > > Pat > > > Pat, Sorry OM, I was talking about the "Loosiana Loop", an inverted delta loop on a PVC mast. This one's on p. 32. Article: 227149 of rec.radio.amateur.antenna From: "kb9rqz@hotmail.com" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 25 Jul 2006 11:28:39 -0700 Message-ID: <1153852119.194366.137430@b28g2000cwb.googlegroups.com> References: Bill Turner wrote: > ORIGINAL MESSAGE: > > On 25 Jul 2006 10:12:17 -0700, "RHF" > wrote: > > >I give Honor and Respect to any Amateur Radio {Ham} Operator : > >Who has built and uses his own Receiver and CW Transmitter > >for regular CW use. I will gladly read their posts and listen to > >their arguments as to "Why" CW is important to the ARS. > >- BUT - "IF" all they have every done is bought ready-made > >equipment and claim that CW is necessary to the ARS > >- please don't waste my time. > > ------------ REPLY SEPARATOR ------------ > > Construction/design skills and operating skills are two different > things. What does one have to do with the other? everything if you ask most of the CW advocates > > Did you build your own car? Dishwasher? Toaster? Razor? > > Bill, W6WRT Article: 227150 of rec.radio.amateur.antenna Date: Tue, 25 Jul 2006 14:35:49 -0400 From: jawod Subject: Open-Sleeve Antenna Message-ID: I came across this in the ARRL Antenna Book (p. 7-21) 20th Edition. For such a simple set-up, why haven't I heard of anyone using it? I understand some commercial verticals use this design in some way. From what I have read, the open-sleeve design has a simple lambda/4 vertical with two side vertical elements of given d diameter and distance D from the center vertical (monopole). Given the improvement of SWR bandwidth shown, why isn't this a more popular approach? (or is it, and I just don't know it?) John AB8WH Article: 227151 of rec.radio.amateur.antenna From: "Frank's" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> Subject: Re: Radiating Efficiency Message-ID: Date: Tue, 25 Jul 2006 18:44:03 GMT >> Cecil, that is what I did with NEC, and got an efficiency >> of about 35%. Using the ratio of Rr/(Rr+Rloss) >> produces a totally different answer. >> >> NEC 4 computes a normalized far field, at 1 m, in units >> of volts. NEC 2 incorrectly shows units of V/m. > > W7EL tells us that EZNEC doesn't display the surface > wave which obviously contains power. Would that affect > the efficiency using the integration technique? > -- > 73, Cecil http://www.qsl.net/w5dxp Good point Cecil, I forgot about the surface wave. Will have to find a way of including it. Frank Article: 227152 of rec.radio.amateur.antenna From: Al Klein Subject: Re: You're not a real ham if you never took or passed a Code test. Message-ID: References: <44C6294C.C57BD5EC@mred.com> <12cci3kou98rq35@corp.supernews.com> Date: Tue, 25 Jul 2006 14:46:17 -0400 On Tue, 25 Jul 2006 11:36:06 -0500, "H. Adam Stevens, NQ5H" wrote: >This isn't about creating the best operators, it's about selling the most >junk and having the most votes. But "the hobby will die" and "we need qualified operators" sounds so much nicer than "the manufacturers need more money". Article: 227153 of rec.radio.amateur.antenna From: Al Klein Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Message-ID: References: <2nvkb2hl674dhilld10b4ed1iohvib6ff4@4ax.com> <06Wug.5006$ly.1271@bignews6.bellsouth.net> <8m6xg.49$Mi2.28@fe03.lga> <44c59219$0$2926$ecde5a14@news.coretel.net> <084cc2pa83r32o3ibkvf3ac79o7npu4nfj@4ax.com> <12ccga7n3do8ta0@corp.supernews.com> Date: Tue, 25 Jul 2006 15:02:11 -0400 On Tue, 25 Jul 2006 11:05:27 -0500, "David G. Nagel" wrote: >Remember also that most reps are elected by the few who bother to vote >for them. Most are unopposed. Sort of like politicians. And, like politics, those who don't vote deserve the representatives they get. Article: 227154 of rec.radio.amateur.antenna From: Al Klein Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Message-ID: References: <06Wug.5006$ly.1271@bignews6.bellsouth.net> <8m6xg.49$Mi2.28@fe03.lga> <44c59219$0$2926$ecde5a14@news.coretel.net> <084cc2pa83r32o3ibkvf3ac79o7npu4nfj@4ax.com> <12ccga7n3do8ta0@corp.supernews.com> <1153845074.694631.112920@b28g2000cwb.googlegroups.com> Date: Tue, 25 Jul 2006 15:02:49 -0400 On 25 Jul 2006 09:31:14 -0700, "an old friend" wrote: >anyone that thinks you jion the ARRL and stand for office should >inquire of Carl Stevenson Or Steve Mendelson? Article: 227155 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Choices, Choices, Choices... CW or CB? Date: Tue, 25 Jul 2006 12:00:58 -0700 Message-ID: <4iqcc2l2lqa7fg1mahoma3afors04qm8r8@4ax.com> References: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> <1153852119.194366.137430@b28g2000cwb.googlegroups.com> ORIGINAL MESSAGE: On 25 Jul 2006 11:28:39 -0700, "kb9rqz@hotmail.com" wrote: >> Construction/design skills and operating skills are two different >> things. What does one have to do with the other? >everything if you ask most of the CW advocates ------------ REPLY SEPARATOR ------------ A non-answer. Try again. What does one have to do with the other? Bill, W6WRT Article: 227156 of rec.radio.amateur.antenna Date: Tue, 25 Jul 2006 15:14:26 -0400 From: Dave Subject: Re: Choices, Choices, Choices... CW or CB? References: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> Message-ID: Bill Turner wrote: SNIPPED > > Construction/design skills and operating skills are two different > things. What does one have to do with the other? > > Did you build your own car? Dishwasher? Toaster? Razor? > > Bill, W6WRT :-) Bill, I had a master machinist work for me in the 1960s. He could make ANYTHING!! I asked him if he could make a car. Sure!! His reply: "All I need is a block of steel 6X6X20 feet, a large milling machine, and a large lathe." He was a Ham Radio Operator, Collins stuff of the 60s. /s/ DD W1MCE Article: 227157 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Date: 25 Jul 2006 12:18:01 -0700 Message-ID: <1153855081.190895.69000@h48g2000cwc.googlegroups.com> References: Al Klein wrote: > On 25 Jul 2006 09:31:14 -0700, "an old friend" > wrote: > > >anyone that thinks you jion the ARRL and stand for office should > >inquire of Carl Stevenson > > Or Steve Mendelson? sorry don't know his story I Know Carl stried to stand for ARRL director (midalantic) and was refused a place on the ballot Article: 227158 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: You're not a real ham if you never took or passed a Code test. Date: 25 Jul 2006 12:19:57 -0700 Message-ID: <1153855197.865764.115610@b28g2000cwb.googlegroups.com> References: Al Klein wrote: > On Tue, 25 Jul 2006 11:36:06 -0500, "H. Adam Stevens, NQ5H" > wrote: > > >This isn't about creating the best operators, it's about selling the most > >junk and having the most votes. > > But "the hobby will die" and "we need qualified operators" sounds so > much nicer than "the manufacturers need more money". the hobyy is dying have you been following the threads about ars numbers have you looked at the ages of folks at hamfests although yes the copmanies need a bigg enough market to stay in busness too Article: 227159 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 25 Jul 2006 12:23:07 -0700 Message-ID: <1153855387.106686.133430@b28g2000cwb.googlegroups.com> References: Bill Turner wrote: > ORIGINAL MESSAGE: > > On 25 Jul 2006 11:28:39 -0700, "kb9rqz@hotmail.com" > wrote: > > >> Construction/design skills and operating skills are two different > >> things. What does one have to do with the other? > > > >everything if you ask most of the CW advocates > > ------------ REPLY SEPARATOR ------------ > > A non-answer. Try again. What does one have to do with the other? why try again? that is what is insited on by the CW advocates along with anybody that opposes the requirement is lazy or wnat to turn the ARS into CB no proof no evidence just mantras Id rather answer what does a CW test show about my abilty to operate on HF when I have no intention to ever use CW. I d love an answer to that question but I will nver get it either > > Bill, W6WRT Article: 227160 of rec.radio.amateur.antenna From: dxAce Subject: Re: Choices, Choices, Choices... CW or CB? Date: Tue, 25 Jul 2006 15:27:34 -0400 Message-ID: <44C670A6.43A73803@milestones.com> References: an old freind wrote: > Bill Turner wrote: > > ORIGINAL MESSAGE: > > > > On 25 Jul 2006 11:28:39 -0700, "kb9rqz@hotmail.com" > > wrote: > > > > >> Construction/design skills and operating skills are two different > > >> things. What does one have to do with the other? > > > > > > >everything if you ask most of the CW advocates > > > > ------------ REPLY SEPARATOR ------------ > > > > A non-answer. Try again. What does one have to do with the other? > why try again? > that is what is insited on by the CW advocates along with anybody that > opposes the requirement is lazy or wnat to turn the ARS into CB no > proof no evidence just mantras > > Id rather answer what does a CW test show about my abilty to operate on > HF when I have no intention to ever use CW. I d love an answer to that > question but I will nver get it either Face it, you're just lazy. (Besides being horribly retarded). Article: 227161 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 25 Jul 2006 12:30:57 -0700 Message-ID: <1153855856.975478.152870@i3g2000cwc.googlegroups.com> References: dxAce wrote: > an old freind wrote: > > > Bill Turner wrote: > > > ORIGINAL MESSAGE: > > > > > > On 25 Jul 2006 11:28:39 -0700, "kb9rqz@hotmail.com" > > > wrote: > > > > > > >> Construction/design skills and operating skills are two different > > > >> things. What does one have to do with the other? > > > > > > > > > >everything if you ask most of the CW advocates > > > > > > ------------ REPLY SEPARATOR ------------ > > > > > > A non-answer. Try again. What does one have to do with the other? > > why try again? > > that is what is insited on by the CW advocates along with anybody that > > opposes the requirement is lazy or wnat to turn the ARS into CB no > > proof no evidence just mantras > > > > Id rather answer what does a CW test show about my abilty to operate on > > HF when I have no intention to ever use CW. I d love an answer to that > > question but I will nver get it either > > Face it, you're just lazy. (Besides being horribly retarded). you are just the prooof I need to make my point about why the Hobby is in trouble Article: 227162 of rec.radio.amateur.antenna Date: Tue, 25 Jul 2006 15:32:39 -0400 From: Dave Subject: Re: You're not a real ham if you never took or passed a Code test. References: <44C6294C.C57BD5EC@mred.com> <12cci3kou98rq35@corp.supernews.com> Message-ID: Al Klein wrote: > On Tue, 25 Jul 2006 11:36:06 -0500, "H. Adam Stevens, NQ5H" > wrote: > > >>This isn't about creating the best operators, it's about selling the most >>junk and having the most votes. > > > But "the hobby will die" and "we need qualified operators" sounds so > much nicer than "the manufacturers need more money". Listen! "THE MANUFACTURERS NEED MORE MONEY." "THE MANUFACTURERS NEED BIGGER MARKETS." "THE MANUFACTURERS NEED MORE ..." Design and manufacture of any electronics item requires a market to recover design costs, to recover manufacturing tooling costs, to cover distribution costs, to provide a return on investment, to provide a return on equity, to provide net profits to cover medical insurance, to provide net profits for stock retirement plans, to feed the engine of the economy. The cost of a single DSP chip that operates at high i.f. frequencies has to be recovered or the chip designer goes BANKRUPT. How many radios must be sold to recover a million dollar investment in a single chip? "THE MANUFACTURERS NEED BIGGER MARKETS." Follow the money. Understand our hobby/public service! Finally then, the question becomes not whether we are appliance operators [most of us are], but do we wish to advance the radio art? "How do we advance the radio art?" is a complex question with many answers. Is preserving historic skills part of the art? Is operating AM, when most HF is SSB, part of the art? Is ragchewing part of the art? Is EME part of the art? Is old fashioned RTTY part of the art? Is current digital communication part of the art [most of today's digital is actually ancient]? I say NO! But, taking the time, using the energy to learn, investing our money in technology and learning that technology is contributing to the art. Or, is it? /s/ DD W1MCE Article: 227163 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: Radial attenuation Message-ID: <1oscc2l66g8l0s1fdov2khphc0sfsumo83@4ax.com> References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> Date: Tue, 25 Jul 2006 15:38:37 -0400 On Tue, 25 Jul 2006 11:11:28 -0700, Richard Clark wrote: >On Tue, 25 Jul 2006 12:32:49 -0400, Walter Maxwell >wrote: > >> you either skimmed BLE too quickly, or the Alzhiemers >>effect had already taken place. > >Hi Walt, > >Reggie's only defense against plagiarism (a charge he loves to bandy >about) is claiming to have NOT read BLE. It mimics his railing >against software users as intellectual cripples when he has a trove of >software offered like dope to school children on the playground. > >Reggie, > >It is amazing how you can spit in the faces of those commending you >for your software; and you do it with full vigor and glee. You may >want to ponder your legacy as a maker of crutches (un-referenced >executables) or leaving a testimony in open source code. Even with >these positive examples you sneer at your source to gain the >rhetorical advantage, and yes, that makes you a troll (and this is >decidedly different from what the Brit's call eccentrics, or what we >call characters). > >The one complaint I've heard frequently from you when you are asked to >write something comprehensive (there are models in history from >Heavysides that you similarly dismiss) is that there is not enough >time. You seem to have plenty enough time to anticipate my banter, or >to otherwise respond to/with trivialities. This has got to be the >height of decadence. > >73's >Richard Clark, KB7QHC Richard, what a masterful discourse on Reggie's character, oops, I mean eccentricities! Quite similarly, your earlier admonition to his lack of appreciation of BLE in your stately defense of it as a document worthy of Lord Kelvin. Bravo! Walt, W2DU Article: 227164 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Cutting cable length to match 1/4 wave 162 MHz antenna? Date: Tue, 25 Jul 2006 12:48:57 -0700 Message-ID: <9ctcc2dgp8k9qpkt8nhttoqmidambg1ufq@4ax.com> References: <59ywg.3365$bP5.367@newsread1.news.pas.earthlink.net> On Tue, 25 Jul 2006 11:12:44 -0700, Bill Turner wrote: >ORIGINAL MESSAGE: > >On Tue, 25 Jul 2006 15:38:04 +0200, Helmut Wabnig > <...._.--_.-_-..._-._.._--.@.-_---_-._*_.-_-> wrote: > >>Side note: >>Did you note I left out the receiver? >>Does anybody know the input impedance of his receivers in use? >>How would you measure the input impedance? > >------------ REPLY SEPARATOR ------------ > >I would think a MFJ SWR analyzer would do it. Haven't tried it, but >can't think of a reason why it wouldn't work. Hi Bill, Good suggestion. 73's Richard Clark, KB7QHC Article: 227165 of rec.radio.amateur.antenna From: "cmdr buzz corey" Subject: Re: You're not a real ham if you if you keep advocating killing the ARS Date: 25 Jul 2006 12:53:00 -0700 Message-ID: <1153857180.567775.169920@75g2000cwc.googlegroups.com> References: an old idiot wrote: > sure it is a hobby with service related aspects rather the Boy Scouts > are supposed to be Cite one place in part 97, which defines amateur radio, where it is called a hobby. Article: 227166 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: You're not a real ham if you if you keep advocating killing the ARS Date: 25 Jul 2006 12:56:52 -0700 Message-ID: <1153857412.613487.278630@h48g2000cwc.googlegroups.com> References: cmdr buzz corey wrote: > an old idiot wrote: > > > sure it is a hobby with service related aspects rather the Boy Scouts > > are supposed to be > > Cite one place in part 97, which defines amateur radio, where it is > called a hobby. red herring alert Part 97 does not define Ham radio, Part 97 defines the rules WE define Ham radio Article: 227167 of rec.radio.amateur.antenna From: "Frank's" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> Subject: Re: Radiating Efficiency Message-ID: Date: Tue, 25 Jul 2006 19:58:03 GMT >> W7EL tells us that EZNEC doesn't display the surface >> wave which obviously contains power. Would that affect >> the efficiency using the integration technique? >> -- >> 73, Cecil http://www.qsl.net/w5dxp > > Good point Cecil, I forgot about the surface wave. Will have to > find a way of including it. As usual, reading manuals would really help. It seems that I4, a four digit integer, in the RP card, can provide the necessary information. With a 9 m monopole, and 36 10 m radials, 25 mm below ground. All wires #14 AWG. The radiation efficiency is 32% at 8.07 MHz (Antenna resonant frequency). Frank RP 0 19 73 1002 -90 0 5.00000 5.00000 Article: 227168 of rec.radio.amateur.antenna From: "RHF" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 25 Jul 2006 13:40:18 -0700 Message-ID: <1153860018.027583.116140@75g2000cwc.googlegroups.com> References: BT - One Word : "Amateur" {Ham} as in Operator ~ RHF All 'others' for the most part are 'appliance operators' just like so many CB'ers - IMHO. . . . . Bill Turner wrote: > ORIGINAL MESSAGE: > > On 25 Jul 2006 11:28:39 -0700, "kb9rqz@hotmail.com" > wrote: > > >> Construction/design skills and operating skills are two different > >> things. What does one have to do with the other? > > > >everything if you ask most of the CW advocates > > ------------ REPLY SEPARATOR ------------ > > A non-answer. Try again. What does one have to do with the other? > > Bill, W6WRT Article: 227169 of rec.radio.amateur.antenna From: Timothy@tholtom.freeserve.co.uk Subject: Newbie Question: HELP!! Antenna Noise Date: 25 Jul 2006 13:54:49 -0700 Message-ID: <1153860889.661316.158250@m73g2000cwd.googlegroups.com> I decided to try one of the simplest of antennas, a quarter wave vertical for 20m supported by a roach pole. I live on the 9th (top) floor of an appartment block, with a balcony. The balcony is surrounded by a a metal railing which I decided to use as the counterpoise. I have a portable communications receiver with a small helical antenna. Obviously this gives limited performance with this antenna... Anyway, hooked up the antenna to 50 Ohm coax and connected the other end to the comms receiver. Result? Noise at about 8 S units, all but drowmning out the signal. If I remove the counterpoise, it's even worse, a howling sound. If I short the counterpoise and vertical, the signal is actually BETTER. If I go back to the little helical that comes with the comms receiver, then the noise VANISHES and the signal's not bad either!!! Question: What am I doing wrong? How can I improve the vertical (without moving)? Question: Are there any other antennas that would be better in this situation (9th floor appartment)? Magnetic Loop? Any help anyone can give would be MOST welcome!!!! Tim Article: 227170 of rec.radio.amateur.antenna From: "an old feind" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 25 Jul 2006 14:17:36 -0700 Message-ID: <1153862256.387291.315870@p79g2000cwp.googlegroups.com> References: RHF wrote: > Slow Code wrote: > > That's what you have to decide. > > > > SC > > SC - 10-4 Good Buddy ! :o) ~ RHF > > I give Honor and Respect to any Amateur Radio {Ham} Operator : > Who has built and uses his own Receiver and CW Transmitter > for regular CW use. I will gladly read their posts and listen to > their arguments as to "Why" CW is important to the ARS. > - BUT - "IF" all they have every done is bought ready-made > equipment and claim that CW is necessary to the ARS > - please don't waste my time. BTW any coment on No tech has bulilt and uses (when he can someone else to talk ) a ^M AM rig one tube and all old type of design (based on an old ham 5 meter unit) > . > . > . . Article: 227171 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Newbie Question: HELP!! Antenna Noise Date: Tue, 25 Jul 2006 14:39:23 -0700 Message-ID: References: <1153860889.661316.158250@m73g2000cwd.googlegroups.com> On 25 Jul 2006 13:54:49 -0700, Timothy@tholtom.freeserve.co.uk wrote: >I decided to try one of the simplest of antennas, a quarter wave >vertical for 20m supported by a roach pole. > >I live on the 9th (top) floor of an appartment block, with a balcony. >The balcony is surrounded by a a metal railing which I decided to use >as the counterpoise. > >I have a portable communications receiver with a small helical antenna. > Obviously this gives limited performance with this antenna... > >Anyway, hooked up the antenna to 50 Ohm coax and connected the other >end to the comms receiver. > >Result? Noise at about 8 S units, all but drowmning out the signal. >If I remove the counterpoise, it's even worse, a howling sound. If I >short the counterpoise and vertical, the signal is actually BETTER. If >I go back to the little helical that comes with the comms receiver, >then the noise VANISHES and the signal's not bad either!!! > >Question: What am I doing wrong? How can I improve the vertical >(without moving)? > >Question: Are there any other antennas that would be better in this >situation (9th floor appartment)? Magnetic Loop? > >Any help anyone can give would be MOST welcome!!!! > > >Tim Hi Tim, You give a very good description of your problem. There's more that could be said, but it starts very well. First, we can start with what is good. You get no noise and a good signal with your little helical. I presume this is a battery operated set, or could be battery operated. If not, connect it to an extension line (but try to go battery operated). Move your set to the balcony and see if the noise returns. If so, use the set to try and locate the noise. If not, then your problem is between where you are listening and where the new antenna is going to be. Try tracing that path back while monitoring on your set to see if any noise sources are along the way (this is unlikely, and shielded coax should take care of it). If so, we will discuss this below. If not, then my bet is your noise will be discovered in the next test. Put your set back into its usual operating area. Connect the coax to the set. Disconnect the coax from both the balcony and the antenna (the far end of the coax is just floating - don't let it touch any metal) and check for noise. If not, you are ready for the next test. If so, the problem may still be related to the next test, but I would bet your coax is connected to something metallic along the way. Connect JUST the coax shield to the rail of your balcony. If you get noise AND your set is plugged in (try this too, if you normally use it with AC power); then you have a ground loop, or conducted noise. You can retain the "ground" side of the antenna with the rail, if you insert a capacitor between the coax shield and the rail. However, this is a Hail Mary kinda of solution and will not be entirely satisfactory. If you don't get the noise through this one connection and finishing with a connection to the antenna does, then there is one more thing you can do. At the antenna end, coil the coax with about 8 - 12 turns around a coffee can or large canister or 2 liter pop bottle just before the bitter end where connections are made. If this reduces the noise, that noise is arriving from somewhere along the path and being coupled into the line at the antenna. Alternatively, your set may need grounding too. Problem here is that you are a long way from RF ground (9 floors away), and that need for ground is more a need for shielding around the set. All of this argues local noise, so it serves your interest to find it. One quick way is to kill power to the entire building and successively add it back until the noise reappears. This, of course, is a fantasy; but you could do it for your own apartment at the breaker panel. If you still have noise in a dead apartment (battery operation of course); then you have problematic neighbors. This still demands that you haul that set around snooping for the source of noise. If the noise went away, sometimes it arrives from a distant source (in the apartment) that SHARES the same breaker (other side of the wall?). If so, experiment with plugging your set into other outlets on different breakers (use an extension line so that you don't have to move the set). If we have to return to the balcony rail as the culprit, then build two antennas and connect one to the coax shield, one to the coax inner conductor, make the coil described above (or look for a 1:1 current balun), and make SURE that nothing touches the railing, electrically. 73's Richard Clark, KB7QHC Article: 227172 of rec.radio.amateur.antenna From: nm5k@wt.net Subject: Re: Open-Sleeve Antenna Date: 25 Jul 2006 14:50:03 -0700 Message-ID: <1153864203.266672.55110@i42g2000cwa.googlegroups.com> References: jawod wrote: > I came across this in the ARRL Antenna Book (p. 7-21) 20th Edition. > > For such a simple set-up, why haven't I heard of anyone using it? > > I understand some commercial verticals use this design in some way. > > From what I have read, the open-sleeve design has a simple lambda/4 > vertical with two side vertical elements of given d diameter and > distance D from the center vertical (monopole). > > Given the improvement of SWR bandwidth shown, why isn't this a more > popular approach? (or is it, and I just don't know it?) > > John > AB8WH Sleeve vertical dipoles are quite common, but I don't get the description of two vertical side elements...?? The usual sleeve vertical is a 1/4 wave radiator, and a 1/4 wave tube, open on the bottom, as the lower half of the antenna. The better designs use a second 1/4 wave sleeve as a decoupling section. These antennas are pretty prone to common mode spillover if you don't use a lower decoupling section. The coax runs up the middle of both sleeves. The shield of the coax is connected to the top closed end of the lower decoupling sleeve. Open at the bottom, same as the sleeve above it that is the lower half of the antenna. A company named "Dodge" used to make those for many commercial users. IE: police, etc.. I think it was Dodge anyway.. The design has been around a long time. MK Article: 227173 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Is It double bazooka less noisy? References: <1153105845.609970.257280@h48g2000cwc.googlegroups.com> <12btggnfvuof911@corp.supernews.com> <8VLvg.10483$2v.1274@newssvr25.news.prodigy.net> <1153433788.383801.90830@75g2000cwc.googlegroups.com> <1153445174.176522.120710@75g2000cwc.googlegroups.com> <12c27qui0r4ohb8@corp.supernews.com> <3e9xg.11685$2v.4048@newssvr25.news.prodigy.net> <1153828704.177146.42840@m73g2000cwd.googlegroups.com> <12cci71i2kp027d@corp.supernews.com> <12ccm30e6qt3e67@corp.supernews.com> Message-ID: Date: Tue, 25 Jul 2006 21:59:54 GMT > "Cecil Moore" wrote in message >> I don't remember the bazooka ever being discussed before >> in the context of precipitation static so it is essentially >> a brand new topic. H. Adam Stevens, NQ5H wrote: > Actually, I recall your mentioning it before, Cecil. Couldn't be. I didn't know what the schematic was for a double bazooka until I looked it up last week. The double bazooka uses the same techniques that are used on airplanes to reduce precipitation static. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227174 of rec.radio.amateur.antenna Date: Tue, 25 Jul 2006 18:04:05 -0400 From: jawod Subject: Re: QST's Louisiana Loop References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> Message-ID: jawod wrote: > I am considering building the Louisiana loop shown in this month's QST. > It is basically an inverted delta loop. I don't know if I can model it > on EZNEC (I guess I can...but I've only progressed through a dipole or > two). > > I actually intend to string it up among some trees in the backyard in a > sort of temporary fashion. > > Realizing the directionality involved, I will aim it toward Asia over > Alaska. > > Now, any caveats or recommendations or ? before I embark on my first > antenna build? > > I don't at present even know the feedpoint impedance but I intend to use > RG8U for feedline if that's possible. There is no mention of an UNUN or > Balun in the article. > > What do youse think? Thinks? > > John > AB8WH > > PS, I'll give the hoberman sphere a rest for a while (hi) Well, here's something new...responding to my own post (sort of) As I started to collect parts needed for this antenna, I realize that lightweight aluminum tubing at 7/8, 3/4 and 5/8 inches is not available >from Loews. What's a good local source for aluminum tubing? Article: 227175 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Newbie Question: HELP!! Antenna Noise References: <1153860889.661316.158250@m73g2000cwd.googlegroups.com> Message-ID: Date: Tue, 25 Jul 2006 22:10:32 GMT Timothy@tholtom.freeserve.co.uk wrote: > I decided to try one of the simplest of antennas, a quarter wave > vertical for 20m ... > Result? Noise at about 8 S units, all but drowmning out the signal. That corresponds to my experience with verticals at my QTH. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227176 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: QST's Louisiana Loop Date: Tue, 25 Jul 2006 15:15:01 -0700 Message-ID: References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> On Tue, 25 Jul 2006 18:04:05 -0400, jawod wrote: >What's a good local source for aluminum tubing? Hi John, Look in the yellow pages for "metal shorts." 73's Richard Clark, KB7QHC Article: 227177 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Open-Sleeve Antenna References: <1153864203.266672.55110@i42g2000cwa.googlegroups.com> Message-ID: <3Mwxg.74656$Lm5.68328@newssvr12.news.prodigy.com> Date: Tue, 25 Jul 2006 22:17:35 GMT nm5k@wt.net wrote: > Sleeve vertical dipoles are quite common, but I don't get the > description of two vertical side elements...?? Actually, one doesn't even need two side elements. One element will function with the outside braid to turn the decoupling section into a balanced 1/4WL stub which functions essentially the same as the unbalanced 1/4WL decoupling sleeve. Such is illustrated on page 26-9, Fig 11, of my 15th edition of The ARRL Antenna Book. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227178 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Open-Sleeve Antenna Date: 25 Jul 2006 15:19:32 -0700 Message-ID: <1153865972.604759.114020@b28g2000cwb.googlegroups.com> References: The open sleeve that AB8WH is referencing is several very closely spaced elements of various lengths around a central element that is directly driven by the feedline. The other elements are very tightly coupled to the driven one because they're so close, and so it's a good construction for broadening SWR bandwidth (several overlapping resonances, elements almost the same length) or making a multi band antenna (several widely spaced resonances, elements widely different lengths) - - - - - - I think some HF multiband yagi manufacturers are using them... I don't remember who. Also, many of the wideband long boom VHF yagi designs have a director that ends up very closely spaced to the driven element, essentially an open sleeve... As to why you don't see more of them? I dunno, there are lots of ways to make a multiband antenna. You could do the same thing out of tubing but do it fan-dipole style and connect them all together. You could use traps and cut out the amount of tubing you need. As far as broadbanding, you typically only need it on the lower bands (80/75m comes to mind) and there you'd be talking the erection of two ~70 foot elements instead of one just to broaden your SWR curve even though running a 3:1 SWR on your line and using the tuner in the rig would add negligble loss. Better to take the other 70 feet of aluminum and space it a half wavelength away from the first and phase them into a broadside/endfire array. I think the dimensions are a bit critical like a parallel multiband dipole can be... lots of interaction between the elements. I don't think they've got much of a marketing advantage right now, either. Otherwise "open sleeve" would be an oft-heard buzzword in antenna ads something like "linear loaded" or "no lossy traps". Certainly an antenna construction worth knowing about, though... I thought about building one when I first saw it too. Also, I was playing with the possibility of adding a 2m yagi to my 6m moxon rectangle the driven element of which would be open sleeve coupled. Haven't had much success getting good front to back on 2m in the model though, so I haven't pursued it. That's not the fault of the open sleeveness... I think I need to start with a known good yagi design first. 73, Dan Article: 227179 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: QST's Louisiana Loop Date: 25 Jul 2006 15:24:02 -0700 Message-ID: <1153866242.633382.134130@b28g2000cwb.googlegroups.com> References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> Which is also where you look if you're trying to protect the genetic integrity of possible future offspring while being exposed to significant electromagnetic radiation. Dan Article: 227180 of rec.radio.amateur.antenna From: jgboyles@aol.com Subject: Re: QST's Louisiana Loop Date: 25 Jul 2006 15:45:47 -0700 Message-ID: <1153867547.794846.13800@i42g2000cwa.googlegroups.com> References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> jawod wrote: > jawod wrote: > > I am considering building the Louisiana loop shown in this month's QST. > > It is basically an inverted delta loop. I don't know if I can model it > > on EZNEC (I guess I can...but I've only progressed through a dipole or > > two). > > > > I actually intend to string it up among some trees in the backyard in a > > sort of temporary fashion. > > > > Realizing the directionality involved, I will aim it toward Asia over > > Alaska. > > > > Now, any caveats or recommendations or ? before I embark on my first > > antenna build? > > > > I don't at present even know the feedpoint impedance but I intend to use > > RG8U for feedline if that's possible. There is no mention of an UNUN or > > Balun in the article. > > > > What do youse think? Thinks? > > > > John > > AB8WH > > > > PS, I'll give the hoberman sphere a rest for a while (hi) > Well, here's something new...responding to my own post (sort of) > > As I started to collect parts needed for this antenna, I realize that > lightweight aluminum tubing at 7/8, 3/4 and 5/8 inches is not available > from Loews. > > What's a good local source for aluminum tubing? If you can't find Aluminum, see if you can get emt conduit in lengths that will work. (heavy) Don't use Aluminum. Hams have been building Quads and Deltas for 60 years using bamboo or fibreglass, with the wire taped or ty-wrapped to the bamboo (fishing pole). You can get the fibreglass from Maxgain if you want to go that route. If you are dead set on duplicating the Author, try Texas Towers, they sell different lengths of Aluminum. Gary N4AST Article: 227181 of rec.radio.amateur.antenna From: "Rayburn" References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> Subject: Re: neighborhood antenna restrictions Date: Tue, 25 Jul 2006 19:18:03 -0400 Message-ID: Copper and aluminum Gutters work great!...If they only run across the front and back of the house you can connect them with a small wire across the roof to make for a nice long antenna! For example I'm hooked to the bottom of a downspout near the ground on my 3 story home....about 28 feet up the guttering starts and runs 25 feet across the back of the house......I connected a wire across the roof (60 feet long) to the end of the front gutter thats the same height and length. 166 feet of antenna in the shape of an upside down U ! I buried a couple of ground radials next to a fence for 160...80....40 and added a few short ones for 20 /15 and 10 about an inch deep in the yard.....works great with a tuner and is fantastic on the L and AM bands for reception as well! Other than a small 4 inch length of coax behind the house next to the garage door.....Its invisible! wrote in message news:1153692686.342597.27820@h48g2000cwc.googlegroups.com... > Help. I've been licensed since 1967, but I haven't been active for > about 20 years. I just bought a FT-101EE with a Cushcraft R4 vertical > antenna, however there are restrictions in my subdivision about > antennas. I'm thinking my best bet may be a long wire between my house > and a neighbor's tree with a tuner. I know this is an ago old battle, > any ideas for an inconspicuous HF antenna? > Article: 227182 of rec.radio.amateur.antenna Date: Tue, 25 Jul 2006 23:32:01 +0000 From: Maxwell Smart #99 Subject: Re: QST's Louisiana Loop Looziana Loops!! References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> <44c4bbd9_1@news.iprimus.com.au> <44c63c89_1@news.iprimus.com.au> <9db61$44c66290$453d9423$19131@FUSE.NET> Message-ID: <44c6a9f8_1@news.iprimus.com.au> jawod wrote: > Maxwell Smart #99 wrote: >> jawod wrote: >> >>> test wrote: >>> >>>> jawod wrote: >>>> >>>>> I am considering building the Louisiana loop shown in this month's >>>>> QST. It is basically an inverted delta loop. I don't know if I >>>>> can model it on EZNEC (I guess I can...but I've only progressed >>>>> through a dipole or two). >>>>> >>>>> I actually intend to string it up among some trees in the backyard >>>>> in a sort of temporary fashion. >>>>> >>>>> Realizing the directionality involved, I will aim it toward Asia >>>>> over Alaska. >>>>> >>>>> Now, any caveats or recommendations or ? before I embark on my >>>>> first antenna build? >>>>> >>>>> I don't at present even know the feedpoint impedance but I intend >>>>> to use RG8U for feedline if that's possible. There is no mention >>>>> of an UNUN or Balun in the article. >>>>> >>>>> What do youse think? Thinks? >>>>> >>>>> John >>>>> AB8WH >>>>> >>>>> PS, I'll give the hoberman sphere a rest for a while (hi) >>>> >>>> >>>> This antenna was meant to be fed as a multiband antenna using open >>>> wire feedline and a tuner. >>>> >>>> Its height dependent. The takeoff angle on 20 is high. I myself >>>> would use a dipole with open wire feedline. However the authors >>>> intentions was for a compact multiband antenna. If you have trees >>>> use the large loop as in the ARRL antenna handbook. >>>> >>>> For a better antenna that feeds with open wire line and that has a >>>> ideal low angle pattern on all band from 20 meters to 10. Look at >>>> the horizontal magnetic slot antenna. You can find details in the >>>> latest RSGB handbook. >>>> >>>> A good tuner for these antennas is the Balanced Tuner by Measures. >>>> >>>> >>>> Pat >>> >>> Pat, >>> Thanks for the input. >>> I have a question. >>> >>> Why do you say that the antenna was meant to be fed using open wire >>> feedline? >>> >>> In the article, it shows an SO239 bulkhead to be attached to RG8U cable. >>> >>> John >>> AB8WH >> >> I Hope we talking about the same antenna? >> >> I am talking about the antenna in this months QST page 38 ZS6AAA >> >> "The Compact Quad Multiband Hf Antenna" August 2006 >> >> So i hope i have not crossed wires here. But this antenna is open wire >> fed, supported on a single fibreglass pole. >> >> >> Pat >> >> >> > Pat, > Sorry OM, I was talking about the "Loosiana Loop", an inverted delta > loop on a PVC mast. This one's on p. 32. No wonder i got confused my brain spell checker did not recognise "Looziana" Pat Article: 227183 of rec.radio.amateur.antenna Date: Tue, 25 Jul 2006 23:37:07 +0000 From: Maxwell Smart #99 Subject: Re: Open-Sleeve Antenna References: Message-ID: <44c6ab27_1@news.iprimus.com.au> jawod wrote: > I came across this in the ARRL Antenna Book (p. 7-21) 20th Edition. > > For such a simple set-up, why haven't I heard of anyone using it? > > I understand some commercial verticals use this design in some way. > > From what I have read, the open-sleeve design has a simple lambda/4 > vertical with two side vertical elements of given d diameter and > distance D from the center vertical (monopole). > > Given the improvement of SWR bandwidth shown, why isn't this a more > popular approach? (or is it, and I just don't know it?) > > John > AB8WH Look in ARRL Antenna Compendium Vol 5. It has a all band 40 to 10 meter parallel fed vertical, while not a open sleeve it can achieve the same objective all bands with no traps. This project is ground mounted. I just wonder what would happen to this all band wonder if raised off the ground? Maybe thats why we see all the Commercial antennas like Hygain and MFJ use all sorts of funny contraptions and transformers on the end of their versions of these antennas. The Hygain Hytower is a similar concept, however not open sleeve. Pat Article: 227184 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Date: 25 Jul 2006 16:38:43 -0700 Message-ID: <1153870723.219035.156660@b28g2000cwb.googlegroups.com> References: Slow Code wrote: > "Dee Flint" wrote in > news:FZ-dnYiba5WU-VjZnZ2dnUVZ_s2dnZ2d@comcast.com: > > > > > Terrible idea. The only way to get ARRL to change is to get involved in > > the politics of ARRL and work to try to effect the changes that you > > want. > > > The ARRL knew what it's members wanted before restructuring through > surveys of the membership, then did you read the proposal that came out > with? Totally opposite of the feeling of the membership. Google it, we > discussed it long and hard years ago when RRAP groupies actually argued > policy. The ARRL is only interested in padding the corporate bank > account, they don't care about the quality of amateurs getting licensed. > Our HF bands can sound like CB if means the ARRL can get more money. The > ARRL BOD stapped Hiram Percy Maxim in the back. The ARRL doesn't care if > you know anything about radio. you mean the ARRL gave in and tired to make a grab for what it thought it could get (coded extra) and failed opening to door for our final victory Article: 227185 of rec.radio.amateur.antenna Subject: Re: You're not a real ham if you if you keep advocating killing the ARS From: Slow Code References: <1153785208.723816.64630@s13g2000cwa.googlegroups.com> <1153857180.567775.169920@75g2000cwc.googlegroups.com> <1153857412.613487.278630@h48g2000cwc.googlegroups.com> Message-ID: <6Wxxg.4662$bP5.4054@newsread1.news.pas.earthlink.net> Date: Tue, 25 Jul 2006 23:36:34 GMT "an old freind" wrote in news:1153857412.613487.278630@h48g2000cwc.googlegroups.com: > > cmdr buzz corey wrote: >> an old idiot wrote: >> >> > sure it is a hobby with service related aspects rather the Boy Scouts >> > are supposed to be >> >> Cite one place in part 97, which defines amateur radio, where it is >> called a hobby. > red herring alert > > Part 97 does not define Ham radio, Part 97 defines the rules > > WE define Ham radio And you want ham radio defined like CB. Ten-Four Good-buddy? Dumbing things down cheapens it, and destroys others enjoyment. Look at the childish bullshit you do in RRAP. You and the other rejects drove everyone away with all your retarded bathroom hummor. That's want will happen with on our HF bands, as it sounds more and more like CB, good hams will give up on it and leave. Many already have. Sc Article: 227186 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: If you had to use CW to save someone's life, would that person die? Date: 25 Jul 2006 16:42:22 -0700 Message-ID: <1153870942.697911.93910@m73g2000cwd.googlegroups.com> References: <1153564701.965658.219410@p79g2000cwp.googlegroups.com> Slow Code wrote: > gsm@mendelson.com (Geoffrey S. Mendelson) wrote in > news:slrnecbne9.muv.gsm@cable.mendelson.com: > > > Al Klein wrote: > > > > 73, > > > > Geoff. > > We don't have to leave or complain if we can improve licensing a little. > That's what's happening here. Striving for quality. indeed we drop the code testing and imporve the quaility right > SC Article: 227187 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 25 Jul 2006 16:45:12 -0700 Message-ID: <1153871112.379896.76980@p79g2000cwp.googlegroups.com> References: Slow Code wrote: > "g. beat" <@> wrote in > news:r7qdnc0nF6FqlVvZnZ2dnUVZ_rCdnZ2d@comcast.com: > > > "Slow Code" wrote in message > > news:pVcxg.9475$vO.1554@newsread4.news.pas.earthlink.net... > >> > >> That's what you have to decide. > >> > >> SC > >> > > > > Personally, I would rather have the First Class and Second Class Radio > > Telephone back. Thank the broadcasters for lobbying to eliminate that > > requirement -- ironic that the industry has been sliding ever since (go > > figure) -- > > That's what happens when you lower standards, why hams don't realize that, > I'll never know. Maybe it's just laziness. no it happens because technolgy is marching on that Hams like you can't face that is the biggest thing wrong with the ARS today > > SC Article: 227188 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: You're not a real ham if you if you keep advocating killing the ARS Date: 25 Jul 2006 16:49:44 -0700 Message-ID: <1153871383.963476.205120@b28g2000cwb.googlegroups.com> References: Slow Code wrote: > "an old freind" wrote in > news:1153857412.613487.278630@h48g2000cwc.googlegroups.com: > > > > > cmdr buzz corey wrote: > >> an old idiot wrote: > >> > >> > sure it is a hobby with service related aspects rather the Boy Scouts > >> > are supposed to be > >> > >> Cite one place in part 97, which defines amateur radio, where it is > >> called a hobby. > > red herring alert > > > > Part 97 does not define Ham radio, Part 97 defines the rules > > > > WE define Ham radio > > > And you want ham radio defined like CB. Ten-Four Good-buddy? if somebody realy wants to use 10 codes I don't care they make as much sense as Q codes > > Dumbing things down cheapens it, and destroys others enjoyment. if it isn't worth it to you to deal with the real world then turn in your license > Look at > the childish bullshit you do in RRAP. You and the other rejects drove > everyone away with all your retarded bathroom hummor. no guess you were not reading stev did it (with help from wismen with years of accusing his foes of various crimes > > That's want will happen with on our HF bands, as it sounds more and more > like CB, good hams will give up on it and leave. Many already have. if you are one of those preparig to leave than good riddance if you can learn some manners you are welcome to stay of course > > Sc Article: 227189 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: is there anybody out thereable to operate CW that would honestly confused a JT65 sig with cw? Date: 25 Jul 2006 16:55:51 -0700 Message-ID: <1153871751.171412.219570@i3g2000cwc.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> Slow Code wrote: > "an old freind" wrote in > news:1153785207.014583.244350@75g2000cwc.googlegroups.com: > code testing > > > > Look like for time on the CSSE I moay need to retake the general > > element but that isn't rough > > > Are you a life member of Handi-Hams? They got a spot for you on the short > bus. no handi ham is downright hostile to all the learn diabilities in my contacts with them > > Sc Article: 227190 of rec.radio.amateur.antenna From: "Bowser" References: <1152992924.187331.312250@i42g2000cwa.googlegroups.com> <12bnls86c2ci3f5@corp.supernews.com> <0vrnb29675p1mcgqgdeljvbbbkji3vkbhl@4ax.com> Subject: Re: Does anyone know of any AC (alternating current) 220V or 350V Shortwave Antenna circuits? Message-ID: Date: Tue, 25 Jul 2006 23:56:18 -0000 My very first short wave experience ever was listening to HCJB on a 6 transistor BCB radio when I was 10 years old...I tweaked the tuning cap to get the thing as far as possible out of the broadcast band range and the overload from the rural above-ground telephone lines did the rest. Got me started thinking that there just might be radios in other countries, hi hi. "Buck" wrote in message news:0vrnb29675p1mcgqgdeljvbbbkji3vkbhl@4ax.com... > On Mon, 17 Jul 2006 18:31:36 -0000, dplatt@radagast.org (Dave Platt) > wrote: > > >In article , > >Buck wrote: > > > >>There used to be radio antennas that plugged into the wall outlets. > >>They had a three pronged connector, but only one side was actually > >>electrically connected, the other prongs were plastic. I am not sure > >>what they did to isolate the electrical from the radio, but the > >>antenna used the house wiring for an antenna extension. > >> > >>This may be what he is looking for, something that coupled with the > >>electrical wires for a longer antenna. > > > >Ugh. Those things. "Turn your entire house into a gigantic > >television antenna!" > > > >These devices usually just couple one of the wires in the outlet to > >the antenna lead, using a small high-voltage capacitor. Component > >parts cost was a few cents, plus the cost of the plug, and (usually) > >some intricately-shaped plastic case meant to make the device look > >sophisticated. The case probably cost more than the guts, and the > >advertised price was far greater than either. > > > >From all I've heard, they generally gave poor performance for at least > >two reasons: > > > >- A house's power wiring is an excellent vehicle for RF noise and > > hash... harmonics from power-supply rectifier, broadband impulse > > noise from any AC motor with brushes, and so forth. Result: lots > > of static in the picture. > > > >- Multipath. The house wiring is of a complex shape, much larger > > than a typical TV antenna. The TV or radio signal is likely to be > > picked up by several different portions of the wiring, which will > > mix (with varying amounts of time delay) at the coupler. Result: > > a ghosty picture. > > > >To paraphrase a Monty Python sketch concerning a particular Australian > >table wine: "This is not a technology for using. This is a > >technology for laying down and avoiding." > > > That sounds like what I was describing. I had an experience once > where there was a drop cord hanging in a loop shape from a power line > that lit up a boat pier about 100 feet long or so. When I put my > shortwave radio near it, I had tremendous reception on MW or SW. I > didn't need to even use the antenna on the radio. I figure there was > about 300 total feet of wire the way it was run. Had a great night > fishing and listening to SWB. > > Buck > -- > 73 for now > Buck > N4PGW Article: 227191 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> Subject: Re: Radiating Efficiency Date: Wed, 26 Jul 2006 00:52:35 +0100 Message-ID: "Frank's" wrote > >> W7EL tells us that EZNEC doesn't display the surface > >> wave which obviously contains power. Would that affect > >> the efficiency using the integration technique? ====================================== The surface or ground wave is the most important fraction of total radiated power. The correct radiation pattern of a vertical antenna shows maximum radiation along the ground. Angle of maximum radiation = 0 degrees. When deducing efficiency, to omit power radiated along the ground from the hemispherical integration will result in serious error. ( Efficiency by NEC4 ) / ( Efficiency by formula ) = 0.38 I can imagine other losses in addition to loss in the radials but to have the other losses several times greater is a bit much. Where are these large losses? Are they in the soil surface - the only other candidate? ---- Reg. Article: 227192 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Open-Sleeve Antenna Date: 25 Jul 2006 17:20:40 -0700 Message-ID: <1153873240.087451.237240@p79g2000cwp.googlegroups.com> References: The commercial manufacturers use all kinds of contraptions to make their antennas look like something you have to buy instead of build. Article: 227193 of rec.radio.amateur.antenna From: "Jack Ricci" Subject: Re: You're not a real ham if you if you keep advocating killing the ARS Date: Tue, 25 Jul 2006 20:21:59 -0400 Message-ID: References: <1153785208.723816.64630@s13g2000cwa.googlegroups.com> <1153857180.567775.169920@75g2000cwc.googlegroups.com> <1153857412.613487.278630@h48g2000cwc.googlegroups.com> <6Wxxg.4662$bP5.4054@newsread1.news.pas.earthlink.net> Regarding Ham Hobby : ... --- ... ... --- ... ... --- ... ... --- ... ... --- ... ... --- ... ... --- ... ... --- ... Jack "Slow Code" wrote in message news:6Wxxg.4662$bP5.4054@newsread1.news.pas.earthlink.net... > "an old freind" wrote in > news:1153857412.613487.278630@h48g2000cwc.googlegroups.com: > >> >> cmdr buzz corey wrote: >>> an old idiot wrote: >>> >>> > sure it is a hobby with service related aspects rather the Boy Scouts >>> > are supposed to be >>> >>> Cite one place in part 97, which defines amateur radio, where it is >>> called a hobby. >> red herring alert >> >> Part 97 does not define Ham radio, Part 97 defines the rules >> >> WE define Ham radio > > > And you want ham radio defined like CB. Ten-Four Good-buddy? > > Dumbing things down cheapens it, and destroys others enjoyment. Look at > the childish bullshit you do in RRAP. You and the other rejects drove > everyone away with all your retarded bathroom hummor. > > That's want will happen with on our HF bands, as it sounds more and more > like CB, good hams will give up on it and leave. Many already have. > > Sc Article: 227194 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Radiating Efficiency Date: 25 Jul 2006 17:50:43 -0700 Message-ID: <1153875043.542959.107250@m73g2000cwd.googlegroups.com> References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> This thread is getting interesting... Reg, your point that the resonant radial effects are more pronounced at higher frequencies makes me think that a small experiment might be in order. A 21MHz or so ground mounted monopole with a small radial field would be a minimal investment in materials to do a BLE style empirical investigation, at least compared to that at 3MHz. It wouldn't be a minimal investment in time but might be an interesting experiment. Given that it would be an epic challenge to measure field strength at a grid of points on a hemisphere surrounding the monopole, I imagine a single point field strength measurement would be an acceptable metric? Thoughts on doing the measurement? I guess BLE would be a good guide for the empiricist. Dan Article: 227195 of rec.radio.amateur.antenna From: "Dee Flint" References: <1151356286.883560.56280@i40g2000cwc.googlegroups.com> <44a05784$0$15331$892e7fe2@authen.yellow.readfreenews.net> <29GdnQxiI6gLuSTZnZ2dnUVZ_t-dnZ2d@comcast.com> <34kdfo.sdf04sffs@devner.net> <2nvkb2hl674dhilld10b4ed1iohvib6ff4@4ax.com> <06Wug.5006$ly.1271@bignews6.bellsouth.net> <8m6xg.49$Mi2.28@fe03.lga> Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Date: Tue, 25 Jul 2006 20:59:30 -0400 Message-ID: "Slow Code" wrote in message news:SVxxg.4658$bP5.2159@newsread1.news.pas.earthlink.net... > "Dee Flint" wrote in > news:FZ-dnYiba5WU-VjZnZ2dnUVZ_s2dnZ2d@comcast.com: > >> >> "Slow Code" wrote in message >> news:uVcxg.9478$vO.5615@newsread4.news.pas.earthlink.net... >>> "Brian Hill" wrote in news:8m6xg.49$Mi2.28@fe03.lga: >>> >>>> >>>> "Al Klein" wrote in message >>>> news:gijob2paistn335sjmffjab7mv493cmm3g@4ax.com... >>>>> On Mon, 17 Jul 2006 19:40:52 -0500, jakdedert >>>>> wrote: >>>>> >>>>>>Al Klein wrote: >>>>> >>>>>>> Then, as the courts would say, you have no standing in the matter. >>>>> >>>>>>Ahh...but I did, once >>>>> >>>>> But you don't now, and it's now now, it's not once. >>>>> >>>>>>proving that one has little to do with the other. >>>>> >>>>> And that you have little to do with this conversation. >>>> >>>> You can argue till your blue in the face but CW requirement will be >>>> gone sooner or later. I fully understand the points of the pro CW guys >>>> but it's just the sign of the times. >>>> >>>> BH >>> >>> >>> We have to keep trying to save Ham radio while we still can because >>> once it's all the way in the shitter it will be even harder to pull >>> back out & clean up. >>> >>> A Ham who'll stand for nothing will sit for anything. I won't accept >>> more dumbing down. >>> >>> >>> Help save Ham radio: >>> >>> >>> 1- No more automatic renewals. Individuals must retest and pass all >>> elements required for their license class every ten years. >>> >> >> No reason to. This has never existed in the history of amateur radio >> and there is no reason to think it would improve things. > > > Yah friggen right, NOT! Continuing to stay knowledgable and re-testing > won't improve things? Sheesh!! What's your problem then, If licensees > remembered what was on their exams ten years ago passing the exams again > should be a breeze. Of course, if they don't rememeber, they'll have to > study again. This will make better hams. And the fact that this > requirement has never existed in the history of ham radio doesn't make it > a bad idea. You're just Lazy. > > Not hardly. Every time they change the pool, I get an up-to-date study guide just to keep current and see what's new. Could pass the test any day of the week and twice on Sunday. By the way the exam has changed in 10 years. There is some common stuff but there is also new stuff. However, the biggest problem would be manpower for conducting the tests. Based on the current number of hams, that would be over 60,000 people retesting every year. The existing test system (and the prior systems when things were administered by the FCC) were all designed around the single testing concept. Essentially, it would mean almost every VE team would need to conduct test sessions weekly or hold huge test sessions monthly. There just aren't enough of us to do that. Plus many facilities now charge for the use of the facility. And the bigger the room, the higher the fee. >>> >>> 2- The passing score for written exams needs to be raised to 85%. >>> >> >> Might be OK. > > > Thank you. > > >>> >>> 3- Code elements should be 13 wpm for General, and 20 wpm for Extra. >>> >> >> Probably wouldn't make a real difference either way. > > > It DOES make a difference. It maintains the number of ways we can > exchange information, and as a filter to keep out some of the riff-raff > allowing you better enjoyment of the service. > I believe in keeping a basic test simply because a person can't determine if they will like code until they've tried it. Plus it is one of the basics of radio. If they have the basics and have thus learned it is not a big, scary hurdle, they will be willing to pursue it in the future since they already know it at a basic level. The filter argument, I consider totally bogus. Code is either a basic part of ham radio or it is not. That should be the criteria for determining if it should be tested. > >>> >>> 4- Make the no-code license one year non-renewable. >>> >> >> Probably wouldn't make any difference. > > Of course it WILL make a difference! It creates an incentive to keep > studying and building on radio knowledge & skill by requiring an upgrade > after a year. And we end up with more knowledgable hams. How can that be > bad? > In today's climate, it will not be an incentive. Those who want to upgrade don't need the non-renewability clause. The rest will simply let their licenses lapse. Those who would let it lapse aren't on the air enough to contribute anyway. > >>> >>> 5- Cancel your ARRL membership until they decide to work to improve >>> things and stop them from proposing ham radio that is like CB. >>> >> >> Terrible idea. The only way to get ARRL to change is to get involved in >> the politics of ARRL and work to try to effect the changes that you >> want. > > > The ARRL knew what it's members wanted before restructuring through > surveys of the membership, then did you read the proposal that came out > with? Totally opposite of the feeling of the membership. Google it, we > discussed it long and hard years ago when RRAP groupies actually argued > policy. The ARRL is only interested in padding the corporate bank > account, they don't care about the quality of amateurs getting licensed. > Our HF bands can sound like CB if means the ARRL can get more money. The > ARRL BOD stapped Hiram Percy Maxim in the back. The ARRL doesn't care if > you know anything about radio. > So why don't you go run for office and promote your platform? Or form your own lobbying group? Complaining here won't get it done. If you want your platform to prevail, the YOU have to do the work to convince people. While the ARRL proposal was not what I wanted, it did indeed reflect some of the things that a significant percentage wanted. As far as the ARRL padding the corporate bank account, if that is true, then you need to report them to the IRS as non-profit organizations are not allowed to do this. Dee D. Flint, N8UZE Article: 227196 of rec.radio.amateur.antenna Date: Tue, 25 Jul 2006 21:15:55 -0400 From: jawod Subject: Re: QST's Louisiana Loop References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> Message-ID: <689d8$44c6c299$453d9423$11166@FUSE.NET> Richard Clark wrote: > On Tue, 25 Jul 2006 18:04:05 -0400, jawod wrote: > > >>What's a good local source for aluminum tubing? > > > Hi John, > > Look in the yellow pages for "metal shorts." > > 73's > Richard Clark, KB7QHC Whenever I wear metal shorts, my impedance goes WAY up. My wife's permissivity is not up for discussion. Article: 227197 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Newbie Question: HELP!! Antenna Noise Date: Tue, 25 Jul 2006 18:19:17 -0700 Message-ID: <12cdgou17te3laa@corp.supernews.com> References: <1153860889.661316.158250@m73g2000cwd.googlegroups.com> Most small portable receivers are designed to be used with a small antenna. When you connect a large antenna, they can be overwhelmed by signals which are much stronger than they're designed to handle. These can be far from the frequency you're trying to listen to, but the overloaded receiver front end generates many signals at many frequencies, often where you're trying to listen. I've found that when I connect a typical scanner or HT type receiver to a decent dipole, I need to add about 20 dB attenuation between the antenna and receiver before the receiver-generated spurs drop to a tolerable level. This might not be your problem, but I think the chances are good that it is. Roy Lewallen, W7EL Timothy@tholtom.freeserve.co.uk wrote: > I decided to try one of the simplest of antennas, a quarter wave > vertical for 20m supported by a roach pole. > > I live on the 9th (top) floor of an appartment block, with a balcony. > The balcony is surrounded by a a metal railing which I decided to use > as the counterpoise. > > I have a portable communications receiver with a small helical antenna. > Obviously this gives limited performance with this antenna... > > Anyway, hooked up the antenna to 50 Ohm coax and connected the other > end to the comms receiver. > > Result? Noise at about 8 S units, all but drowmning out the signal. > If I remove the counterpoise, it's even worse, a howling sound. If I > short the counterpoise and vertical, the signal is actually BETTER. If > I go back to the little helical that comes with the comms receiver, > then the noise VANISHES and the signal's not bad either!!! > > Question: What am I doing wrong? How can I improve the vertical > (without moving)? > > Question: Are there any other antennas that would be better in this > situation (9th floor appartment)? Magnetic Loop? > > Any help anyone can give would be MOST welcome!!!! > > > Tim > Article: 227198 of rec.radio.amateur.antenna From: "an old feind" Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Date: 25 Jul 2006 21:10:13 -0700 Message-ID: <1153887013.410181.76520@h48g2000cwc.googlegroups.com> References: Dee Flint wrote: > "Slow Code" wrote in message > news:SVxxg.4658$bP5.2159@newsread1.news.pas.earthlink.net... > > "Dee Flint" wrote in > > news:FZ-dnYiba5WU-VjZnZ2dnUVZ_s2dnZ2d@comcast.com: > > > > It DOES make a difference. It maintains the number of ways we can > > exchange information, and as a filter to keep out some of the riff-raff > > allowing you better enjoyment of the service. > > > > I believe in keeping a basic test simply because a person can't determine if > they will like code until they've tried it. Plus it is one of the basics of > radio. If they have the basics and have thus learned it is not a big, scary > hurdle, they will be willing to pursue it in the future since they already > know it at a basic level. meaning you basicaly belive that the Mode must be forced on everyone as mode welfare > > The filter argument, I consider totally bogus. because > > Code is either a basic part of ham radio or it is not. That should be the > criteria for determining if it should be tested. Dee do you seriously support the implied postion that if we end Code tesing we should indeed end Code USE? > > > > >>> > >>> 4- Make the no-code license one year non-renewable. > >>> > >> > >> Probably wouldn't make any difference. > > > > Of course it WILL make a difference! It creates an incentive to keep > > studying and building on radio knowledge & skill by requiring an upgrade > > after a year. And we end up with more knowledgable hams. How can that be > > bad? > > > > In today's climate, it will not be an incentive. Those who want to upgrade > don't need the non-renewability clause. The rest will simply let their > licenses lapse. Those who would let it lapse aren't on the air enough to > contribute anyway. thanks a lot btch Article: 227199 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: You're not a real ham if you if you keep advocating killing the ARS Date: 25 Jul 2006 21:13:41 -0700 Message-ID: <1153887221.771922.128340@i3g2000cwc.googlegroups.com> References: Jack Ricci wrote: > Regarding Ham Hobby : > > ... --- ... ... --- ... ... --- ... ... --- ... ... --- > ... ... --- ... ... --- ... ... --- ... maybe sent that Slow code otherwise known as Mr Stupid (his own choice of nick will getit but I doubt it > > Jack > > "Slow Code" wrote in message > news:6Wxxg.4662$bP5.4054@newsread1.news.pas.earthlink.net... > > "an old freind" wrote in > > news:1153857412.613487.278630@h48g2000cwc.googlegroups.com: > > > >> > >> cmdr buzz corey wrote: > >>> an old idiot wrote: > >>> > >>> > sure it is a hobby with service related aspects rather the Boy Scouts > >>> > are supposed to be > >>> > >>> Cite one place in part 97, which defines amateur radio, where it is > >>> called a hobby. > >> red herring alert > >> > >> Part 97 does not define Ham radio, Part 97 defines the rules > >> > >> WE define Ham radio > > > > > > And you want ham radio defined like CB. Ten-Four Good-buddy? > > > > Dumbing things down cheapens it, and destroys others enjoyment. Look at > > the childish bullshit you do in RRAP. You and the other rejects drove > > everyone away with all your retarded bathroom hummor. > > > > That's want will happen with on our HF bands, as it sounds more and more > > like CB, good hams will give up on it and leave. Many already have. > > > > Sc Article: 227200 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: neighborhood antenna restrictions Date: Tue, 25 Jul 2006 23:14:32 -0500 Message-ID: <12cdr19v6ef346@corp.supernews.com> References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> Rayburn wrote: > Copper and aluminum Gutters work great!...If they only run across the front > and back of the house you can connect them with a small wire across the roof > to make for a nice long antenna! > > For example I'm hooked to the bottom of a downspout near the ground on my 3 > story home....about 28 feet up the guttering starts and runs 25 feet across > the back of the house......I connected a wire across the roof (60 feet long) > to the end of the front gutter thats the same height and length. > > 166 feet of antenna in the shape of an upside down U ! > > I buried a couple of ground radials next to a fence for 160...80....40 and > added a few short ones for 20 /15 and 10 about an inch deep in the > yard.....works great with a tuner and is fantastic on the L and AM bands for > reception as well! > > Other than a small 4 inch length of coax behind the house next to the garage > door.....Its invisible! > wrote in message > news:1153692686.342597.27820@h48g2000cwc.googlegroups.com... > >>Help. I've been licensed since 1967, but I haven't been active for >>about 20 years. I just bought a FT-101EE with a Cushcraft R4 vertical >>antenna, however there are restrictions in my subdivision about >>antennas. I'm thinking my best bet may be a long wire between my house >>and a neighbor's tree with a tuner. I know this is an ago old battle, >>any ideas for an inconspicuous HF antenna? >> > > > Congress just passed and the President signed a Federal Law that stops the CC&R cops from prohibiting flying the American Flag on your property. This means you can have a flag pole (antenna). :) Dave WD9BDZ Article: 227201 of rec.radio.amateur.antenna From: Eric F. Richards Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Date: Tue, 25 Jul 2006 22:31:20 -0600 Message-ID: References: <2nvkb2hl674dhilld10b4ed1iohvib6ff4@4ax.com> <06Wug.5006$ly.1271@bignews6.bellsouth.net> <8m6xg.49$Mi2.28@fe03.lga> <1153789149.679540.21960@b28g2000cwb.googlegroups.com> "Sal M. Onella" wrote: > > I wonder: Did the radio amateur community go through anything like this for > the transition away from spark? > Yes, they did. -- 73, Eric F. Richards, KB0YDN, efricha@dim.com "A few old diehards still blazoned 'Spark Forever!' on their QSL cards..." - from "200 Meters & Down", copyright 1936, ARRL From Nevermind Sat Jul 29 12:02:18 EDT 2006 Article: 227202 of rec.radio.amateur.antenna NNTP-Posting-Date: Tue, 25 Jul 2006 23:42:33 -0500 From: Nevermind (Nevermind@hotmail.com) Newsgroups: rec.radio.amateur.antenna Subject: Icom 746PRO X-Newsreader: NewsLeecher v3.7 Final (http://www.newsleecher.com) Message-ID: <_KSdnVbqJ9Ykb1vZnZ2dnUVZ_omdnZ2d@giganews.com> Date: Tue, 25 Jul 2006 23:42:33 -0500 Lines: 13 X-Trace: sv3-pH0kfmSmCaDpgIMM0ZIfd2pD+n1q5AGtA/MYaNCCtBMHBN9XewZ9eXSOFiqvxVwZgyO6e5wx77/0R62!RRmZL+T8FUfoqVLod6brsvULM6jLHw9VVEeIFj628FU1AgKlLXyyO7owsIFrDxHaBRAzgank X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.32 Path: news.unc.edu!elk.ncren.net!newshub.sdsu.edu!border1.nntp.dca.giganews.com!nntp.giganews.com!local02.nntp.dca.giganews.com!news.giganews.com.POSTED!not-for-mail Xref: news0.isis.unc.edu rec.radio.amateur.antenna:227202 Has anyone purchased a recent ICOM 746PRO radio, and had any problems? I would like to buy one soon, but there seemed to be alot of problems in the early models. I was just wondering how the newer models were holding up. -- --------------------------------- --- -- - Posted with NewsLeecher v3.7 Final Web @ http://www.newsleecher.com/?usenet ------------------- ----- ---- -- - Article: 227203 of rec.radio.amateur.antenna From: "Frank's" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> Subject: Re: Radiating Efficiency Message-ID: <_FCxg.133334$A8.100770@clgrps12> Date: Wed, 26 Jul 2006 05:00:42 GMT "Reg Edwards" wrote in message news:vO-dnVy3APdgMlvZRVnyhg@bt.com... > > "Frank's" wrote >> >> W7EL tells us that EZNEC doesn't display the surface >> >> wave which obviously contains power. Would that affect >> >> the efficiency using the integration technique? > ====================================== > > The surface or ground wave is the most important fraction of total > radiated power. The correct radiation pattern of a vertical antenna > shows maximum radiation along the ground. Angle of maximum radiation = > 0 degrees. > > When deducing efficiency, to omit power radiated along the ground from > the hemispherical integration will result in serious error. > > ( Efficiency by NEC4 ) / ( Efficiency by formula ) = 0.38 > > I can imagine other losses in addition to loss in the radials but to > have the other losses several times greater is a bit much. Where are > these large losses? Are they in the soil surface - the only other > candidate? > ---- > Reg. Correct Reg, I had thought the modified RP card considered ground wave, but it does not. I am working on a combined integration including the surface wave, which should provide a more accurate indication of the overall efficiency. I will also attempt the analysis of various lengths of radial wires. Frank Article: 227204 of rec.radio.amateur.antenna From: markie_morgan_rapesboys@yahoo.com Subject: Re: bless you and may you find peace Date: 26 Jul 2006 04:41:27 -0700 Message-ID: <1153914087.277023.157290@i3g2000cwc.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> an old freind wrote: > Not Cocksucker Lloyd wrote: > > an old freind wrote: > > > Hey Stupid wrote: > > > > "an_old_friend" wrote in > > > > news:1153685459.215393.83880@h48g2000cwc.googlegroups.com: > > > > Look like for time on the CSSE I moay need to retake the general > > > element but that isn't rough > > > > Except you didn't pass it, the VE session sheet proves it. > get over it Mr turd Then quit lying about passing, Mr. Queer. Article: 227205 of rec.radio.amateur.antenna From: markie_morgan_rapesboys@yahoo.com Subject: Re: is there anybody out thereable to operate CW that would honestly confused a JT65 sig with cw? Date: 26 Jul 2006 04:42:45 -0700 Message-ID: <1153914164.987324.219000@s13g2000cwa.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> an old freind wrote: > Slow Code wrote: > > "an old freind" wrote in > > news:1153785207.014583.244350@75g2000cwc.googlegroups.com: > > > code testing > > > > > > Look like for time on the CSSE I moay need to retake the general > > > element but that isn't rough > > > > > > Are you a life member of Handi-Hams? They got a spot for you on the short > > bus. BWHAHAHAHAHA! > no handi ham is downright hostile to all the learn diabilities in my > contacts with them That's because you are a fraud and they know you aren't disabled just illiterate. Article: 227206 of rec.radio.amateur.antenna From: kb9rqz_child_molester@yahoo.com Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers If Necesssary. Date: 26 Jul 2006 05:07:15 -0700 Message-ID: <1153915635.643905.252110@m73g2000cwd.googlegroups.com> References: <1153222719.097047.12500@s13g2000cwa.googlegroups.com> an old freind wrote: > Not Cocksucker Lloyd wrote: > > an old friend wrote: > > > bless > > > > Hey Markie, hear from any state workers recently? BWHAHAHAHAHA! > had a chat with county worker but he was with the road crew So you blow road crew guys on the side of road? Article: 227207 of rec.radio.amateur.antenna From: Al Klein Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Message-ID: References: <06Wug.5006$ly.1271@bignews6.bellsouth.net> <8m6xg.49$Mi2.28@fe03.lga> <1153887013.410181.76520@h48g2000cwc.googlegroups.com> Date: Wed, 26 Jul 2006 08:21:03 -0400 On 25 Jul 2006 21:10:13 -0700, "an old feind" wrote: >Dee Flint wrote: >> I believe in keeping a basic test simply because a person can't determine if >> they will like code until they've tried it. Plus it is one of the basics of >> radio. If they have the basics and have thus learned it is not a big, scary >> hurdle, they will be willing to pursue it in the future since they already >> know it at a basic level. >meaning you basicaly belive that the Mode must be forced on everyone >as mode welfare As opposed to making a ham license something anyone can get merely by asking for one - because, like you, they don't have the intelligence to pass a real test. Article: 227208 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Quarterwave vertical with radials Date: Wed, 26 Jul 2006 05:29:37 -0700 Message-ID: <12ceo1pplv8v4c2@corp.supernews.com> References: <1152578023.253600.314910@m73g2000cwd.googlegroups.com> <1152609735.071204.264590@m79g2000cwm.googlegroups.com> <34ydnZdtyundZy7ZnZ2dnUVZ8qKdnZ2d@bt.com> <12bone4ol8me4a2@corp.supernews.com> <44bc60a1_1@news.iprimus.com.au> David wrote: > I agree that in the coax side, there is no real 0V because the current has a > standing wave. But the transceiver has a DC power supply (normally 12V) that > is controlled or modulated. One side of the power supply is regarded as 0V > and connected to 0V rail of circuits. The modulated side is the RF live that > is connected to the centre contact of transceiver output connector. > > In theory, while transceiver is transmitting, if I touched the outer of the > output connector, I would not expect to get a shock or RF burn. If I touched > the centre contact of output connector, then I would expect to get a shock > or RF burn. Admittedly, I could touch the outer and find that I am close > enough to the centre contact for RF to capacitively couple into me. In real > life, I would never touch the output connector while the rig is > transmitting. > > Does RF live and ground not exist on the output connector of the > transceiver? Begin with a self-contained, battery-powered transmitter. Put a large metal plate on the ground, stand on the plate, and set the radio on the plate. Touch the radio. No burn. Touch the center conductor. Burn. Just like you said. But now put the radio on top of an insulator, and connect the center conductor of the antenna connector to the metal plate. Touch the center conductor. No burn. Touch the radio. Burn. Whoa -- you got burned from "0V" -- the "cold" side! No fair! Finally, insulate the radio and disconnect the center conductor from the plate. Hold on to the radio and touch the center conductor. Burn. Hold on to a wire going to the center conductor. No burn. Touch the radio while you're holding the wire. Burn. You don't prevent a shock by declaring or "regarding" something to be ground or "0V". You do it by connecting it to the same potential as your body. And declaring it to be "live" doesn't cause the burn -- what causes it is that you're touching something that's at a different potential than your body. Roy Lewallen, W7EL Article: 227209 of rec.radio.amateur.antenna Subject: Re: Icom 746PRO From: Bert Hyman References: <_KSdnVbqJ9Ykb1vZnZ2dnUVZ_omdnZ2d@giganews.com> <44c90e0d.3216510@bart.spawar.mil> Message-ID: Date: 26 Jul 2006 12:59:30 GMT me2@privacy.net (Bart Bailey) wrote in news:44c90e0d.3216510@bart.spawar.mil: > In Message-ID:<_KSdnVbqJ9Ykb1vZnZ2dnUVZ_omdnZ2d@giganews.com> > posted on Tue, 25 Jul 2006 23:42:33 -0500, Nevermind wrote: > >>Has anyone purchased a recent ICOM 746PRO radio, and had any >>problems? I would like to buy one soon, but there seemed to be alot >>of problems in the early models. I was just wondering how the newer >>models were holding up. > > I don't think there are any 'newer' 746 models, I pretty sure he's talking about recent production, not a new variant. > maybe you're thinking of the 756 Pro models > the latest being the IC-756 Pro3. -- Bert Hyman | St. Paul, MN | bert@iphouse.com Article: 227210 of rec.radio.amateur.antenna From: Bob Miller Subject: Re: Icom 746PRO Message-ID: References: <_KSdnVbqJ9Ykb1vZnZ2dnUVZ_omdnZ2d@giganews.com> Date: Wed, 26 Jul 2006 13:25:33 GMT On Tue, 25 Jul 2006 23:42:33 -0500, Nevermind (Nevermind@hotmail.com) wrote: >Has anyone purchased a recent ICOM 746PRO radio, and had any >problems? I would like to buy one soon, but there seemed to be alot >of problems in the early models. I was just wondering how the newer >models were holding up. You can check the recent reviews on eHam.net. Also, at the Icom site, they give a lot of ifs/ands/whats in regard to what they've done to beef up certain circuits that were blowing out, but it sounds like you still have to be careful. bob k5qwg Article: 227211 of rec.radio.amateur.antenna From: mike Subject: Gem Quad Date: Wed, 26 Jul 2006 14:27:27 +0100 Message-ID: <2arec29sf7s6801tct4r766ujfppffg4ru@4ax.com> Hi Would anyone using a 2 or 3 element Gem Quad please get in touch to compare notes. Thanks de Mike G4KHG mikeg4khb@btinternet.com Article: 227212 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Choices, Choices, Choices... CW or CB? Date: Wed, 26 Jul 2006 11:11:18 -0500 Message-ID: <16568-44C79426-1070@storefull-3255.bay.webtv.net> References: Slow Code wrote: "That`s what happens when you lower standards,----." Technological progress eliminates the need for operator expertise and close equipment supervision. A First Class Licensed Radiotelephone Operator is no longer justified or needed to constantly supervise a type-accepted broadcast transamitter designed to only operate when it is operating within the rules (no challenge with modern technology). A less technically adept person can tell if operation is normal. Amateur operation is different. Equipment need not be type-accepted, but it must adhere to the rules just the same. An amateur operator is licensed as such and that defines the "amateur radio operator". The "ham" may or may not be interested in experimentation. The only requirement is that he not violate the rules. Difference between amateur and CB radio is CB can be used in business. Amateur radio cannot. CW radiotelegraphy was obsolete when radiotelephony appeared. This is similar to obsolescence of the horse when the motor vehicle appeared. Communications and transportation have moved on but Morse and horse fanatics linger. Amateur radio appliance operators are fine so long as the rules are enforced. We should seek them and welcome them to the hobby. Best regards, Richard Harrison, KB5WZI Article: 227213 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers If Necesssary. Date: 26 Jul 2006 09:47:33 -0700 Message-ID: <1153932453.938671.304910@i42g2000cwa.googlegroups.com> References: <1153222719.097047.12500@s13g2000cwa.googlegroups.com> kb9rqz_child_molester@yahoo.com wrote: may the lord bless and grant you pecae from the mental illness that traps you Article: 227214 of rec.radio.amateur.antenna From: "an old freind" Subject: may the lord bless and grant you pecae from the mental illness that traps you Date: 26 Jul 2006 09:49:16 -0700 Message-ID: <1153932556.725448.110530@75g2000cwc.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> markie_morgan_rapesboys@yahoo.com wrote: may the lord bless and grant you pecae from the mental illness that traps you Article: 227215 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: Elimination of CW is a loss in the number of ways we can communicatewith other. Date: 26 Jul 2006 10:02:44 -0700 Message-ID: <1153933364.118890.188000@75g2000cwc.googlegroups.com> References: Al Klein wrote: > On 25 Jul 2006 21:10:13 -0700, "an old feind" > wrote: > > >Dee Flint wrote: > > >> I believe in keeping a basic test simply because a person can't determine if > >> they will like code until they've tried it. Plus it is one of the basics of > >> radio. If they have the basics and have thus learned it is not a big, scary > >> hurdle, they will be willing to pursue it in the future since they already > >> know it at a basic level. > > >meaning you basicaly belive that the Mode must be forced on everyone > >as mode welfare > > As opposed to making a ham license something anyone can get merely by > asking for one - because, like you, they don't have the intelligence > to pass a real test. no one hass advocated giving a license away except of course procoders like yourself Funny I can mange ee qso's (second one last night) and yet you inist I am unintelgent based on my inabilty to serve as a modem, a machine funtion Article: 227216 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <1153875043.542959.107250@m73g2000cwd.googlegroups.com> Subject: Re: Radiating Efficiency Date: Wed, 26 Jul 2006 18:43:23 +0100 Message-ID: Dan wrote - > A 21MHz or so ground mounted monopole with a small radial field would > be a minimal investment in materials to do a BLE style empirical > investigation, at least compared to that at 3MHz. It wouldn't be a > minimal investment in time but might be an interesting experiment. > > Given that it would be an epic challenge to measure field strength at a > grid of points on a hemisphere surrounding the monopole, I imagine a > single point field strength measurement would be an acceptable metric? > Thoughts on doing the measurement? I guess BLE would be a good guide > for the empiricist. > ======================================== The results of such experiments would probably generate far less interest than BLE's original work and would not be of great use. But somebody might possibly create a reputation out of it. To repeat BLE's experiments at HF, and to be of use, would require measurements to be made over a wide range of frequencies, over various lengths of radials, over various numbers of radials, over a range of soil resistivities and over a range of soil permittivities. Complexity and cost would be enormous. Financial returns would be relatively small. Who would invest in such a project? How many people wishing to erect a 28 MHz vertical over a set of radials need more knowledge than what already exists. Even CB-ers could do it! It would be far more economic, with a guessed understanding of how radials work, to write and dedicate a computer program to do the job. With a little more tidying-up, program Radial_3 would do. And it's FREE to USA citizens. No licence required! ;o) ---- Reg. Article: 227217 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Choices, Choices, Choices... CW or CB? Date: Wed, 26 Jul 2006 11:02:58 -0700 Message-ID: <6ebfc2plbt9ov3o11b2ua1d7cnplitn9jk@4ax.com> References: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> <1153852119.194366.137430@b28g2000cwb.googlegroups.com> <4iqcc2l2lqa7fg1mahoma3afors04qm8r8@4ax.com> <1153855387.106686.133430@b28g2000cwb.googlegroups.com> <44C670A6.43A73803@milestones.com> ORIGINAL MESSAGE: On Tue, 25 Jul 2006 15:27:34 -0400, dxAce wrote: >Face it, you're just lazy. ------------ REPLY SEPARATOR ------------ Laziness is not the issue. It's a question of results gained for the effort expended. Nearly everyone will put a LOT of effort into something if they perceive a useful return on their efforts. CW donesn't so that for most people. Bill, W6WRT Article: 227218 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Choices, Choices, Choices... CW or CB? Date: Wed, 26 Jul 2006 11:05:42 -0700 Message-ID: References: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> ORIGINAL MESSAGE: On Tue, 25 Jul 2006 15:14:26 -0400, Dave wrote: >Bill, I had a master machinist work for me in the 1960s. He could make ANYTHING!! > >I asked him if he could make a car. Sure!! His reply: "All I need is a block of >steel 6X6X20 feet, a large milling machine, and a large lathe." > >He was a Ham Radio Operator, Collins stuff of the 60s. > >/s/ DD W1MCE ------------ REPLY SEPARATOR ------------ The question was not if you "could" build you own car, it was "did" you. Bill, W6WRT Article: 227219 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Icom 746PRO Date: Wed, 26 Jul 2006 11:11:22 -0700 Message-ID: <60cfc21h9i92qkpciiqo2i3pcad9qi7g5a@4ax.com> References: <_KSdnVbqJ9Ykb1vZnZ2dnUVZ_omdnZ2d@giganews.com> ORIGINAL MESSAGE: On Tue, 25 Jul 2006 23:42:33 -0500, Nevermind (Nevermind@hotmail.com) wrote: >Has anyone purchased a recent ICOM 746PRO radio, and had any >problems? I would like to buy one soon, but there seemed to be alot >of problems in the early models. I was just wondering how the newer >models were holding up. ------------ REPLY SEPARATOR ------------ If you go to the Icom website, they acknowledge the problem and have a serial number posted, after which the problem is fixed. That serial number happened a long time ago, so recent production should be ok. Just verify the serial number. Bill, W6WRT Article: 227220 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Choices, Choices, Choices... CW or CB? Date: Wed, 26 Jul 2006 11:11:55 -0700 Message-ID: References: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> <1153852119.194366.137430@b28g2000cwb.googlegroups.com> <4iqcc2l2lqa7fg1mahoma3afors04qm8r8@4ax.com> <1153860018.027583.116140@75g2000cwc.googlegroups.com> ORIGINAL MESSAGE: On 25 Jul 2006 13:40:18 -0700, "RHF" wrote: >BT - One Word : "Amateur" {Ham} as in Operator ~ RHF > >All 'others' for the most part are 'appliance operators' >just like so many CB'ers - IMHO. > . ------------ REPLY SEPARATOR ------------ Nope. It's "Amateur Radio Operator", not "Amateur Radio Constructor". I'll ask again: What does construction skill have to do with operator skill? Bill, W6WRT Article: 227221 of rec.radio.amateur.antenna From: "NA" Subject: FS Antenna coupler Message-ID: Date: Wed, 26 Jul 2006 18:17:04 GMT I have a what looks like a military coupler. Housed in aluminum that is made to evacuate. Motor driven vacuum variable and inductor. I will e-mail photos upon request. $300 plus shipping >from 96701 -- Jim WH6Q Article: 227222 of rec.radio.amateur.antenna From: "Howard W3CQH" References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> Subject: Re: neighborhood antenna restrictions Date: Wed, 26 Jul 2006 15:02:25 -0400 Message-ID: Be sure that the Gutters are not grounded. If you have Aluminum Siding, the gutters maybe attached to the siding. A quick check with an ohmmeter should verify that. Other wise the gutters make a great antenna. "Rayburn" wrote in message news:e204b$44c6a6ab$8b371d4a$30394@ALLTEL.NET... > Copper and aluminum Gutters work great!...If they only run across the > front and back of the house you can connect them with a small wire across > the roof to make for a nice long antenna! > > For example I'm hooked to the bottom of a downspout near the ground on my > 3 story home....about 28 feet up the guttering starts and runs 25 feet > across the back of the house......I connected a wire across the roof (60 > feet long) to the end of the front gutter thats the same height and > length. > > 166 feet of antenna in the shape of an upside down U ! > > I buried a couple of ground radials next to a fence for 160...80....40 and > added a few short ones for 20 /15 and 10 about an inch deep in the > yard.....works great with a tuner and is fantastic on the L and AM bands > for reception as well! > > Other than a small 4 inch length of coax behind the house next to the > garage door.....Its invisible! > wrote in message > news:1153692686.342597.27820@h48g2000cwc.googlegroups.com... >> Help. I've been licensed since 1967, but I haven't been active for >> about 20 years. I just bought a FT-101EE with a Cushcraft R4 vertical >> antenna, however there are restrictions in my subdivision about >> antennas. I'm thinking my best bet may be a long wire between my house >> and a neighbor's tree with a tuner. I know this is an ago old battle, >> any ideas for an inconspicuous HF antenna? >> > > Article: 227223 of rec.radio.amateur.antenna From: kb9rqz_child_molester@yahoo.com Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 26 Jul 2006 12:18:25 -0700 Message-ID: <1153941505.185318.89570@b28g2000cwb.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> an old freind wrote: > may the lord bless and grant you pecae from the mental illness that > traps you May you die in a horrible accident because of brake failure. Article: 227224 of rec.radio.amateur.antenna From: peewee_lloyd_davies@yahoo.com Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 26 Jul 2006 12:24:28 -0700 Message-ID: <1153941868.895869.7640@m73g2000cwd.googlegroups.com> References: an_old_friend wrote: > may the lord bless and grant you reales from the mental illness that > traps you What's "reales?" Article: 227225 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 26 Jul 2006 13:22:03 -0700 Message-ID: <1153945323.126440.31490@m73g2000cwd.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> kb9rqz_child_molester@yahoo.com wrote: > May you die in a horrible accident because of brake failure. you are truly a sicko may the lord bless and grant you pecae from the mental illness that traps you Article: 227226 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 26 Jul 2006 13:25:41 -0700 Message-ID: <1153945541.010776.205600@i42g2000cwa.googlegroups.com> References: <1152903904.823970.155070@b28g2000cwb.googlegroups.com> peewee_lloyd_davies@yahoo.com wrote: may the lord bless and keep you and grant you peace Article: 227227 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 26 Jul 2006 13:30:52 -0700 Message-ID: <1153945852.092539.186360@i3g2000cwc.googlegroups.com> References: Bill Turner wrote: > ORIGINAL MESSAGE: > > On Tue, 25 Jul 2006 15:27:34 -0400, dxAce > wrote: > > >Face it, you're just lazy. > > ------------ REPLY SEPARATOR ------------ > > Laziness is not the issue. It's a question of results gained for the > effort expended. Nearly everyone will put a LOT of effort into > something if they perceive a useful return on their efforts. indeed perosn I spent several 100 hr and got no result for it (except early for the day dectection of my dyslexia) > > CW donesn't so that for most people. > > Bill, W6WRT Article: 227228 of rec.radio.amateur.antenna Subject: Re: Icom 746PRO From: Dave Oldridge References: <_KSdnVbqJ9Ykb1vZnZ2dnUVZ_omdnZ2d@giganews.com> Message-ID: Date: Wed, 26 Jul 2006 21:28:02 GMT Nevermind (Nevermind@hotmail.com) wrote in news: _KSdnVbqJ9Ykb1vZnZ2dnUVZ_omdnZ2d@giganews.com: > Has anyone purchased a recent ICOM 746PRO radio, and had any > problems? I would like to buy one soon, but there seemed to be alot > of problems in the early models. I was just wondering how the newer > models were holding up. A friend of mine locally here tried one. In contest operations it made far too much phase noise over a fairly wide chunk of band, making it a bad actor when other contest stations are operating within a mile or so. He replaced it with a 756Pro and, having used that radio, I would have to say it is probably the 2nd best receiver I've ever had my hands on in more than 40 years of commercial and amateur radio operation (the winner being a $20k Hagenuk). -- Dave Oldridge+ ICQ 1800667 Article: 227229 of rec.radio.amateur.antenna From: Jim - NN7K Subject: Re: Choices, Choices, Choices... CW or CB? References: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> <1153852119.194366.137430@b28g2000cwb.googlegroups.com> <4iqcc2l2lqa7fg1mahoma3afors04qm8r8@4ax.com> <1153855387.106686.133430@b28g2000cwb.googlegroups.com> <44C670A6.43A73803@milestones.com> <6ebfc2plbt9ov3o11b2ua1d7cnplitn9jk@4ax.com> Message-ID: Date: Wed, 26 Jul 2006 22:35:00 GMT > > Laziness is not the issue. It's a question of results gained for the > effort expended. Nearly everyone will put a LOT of effort into > something if they perceive a useful return on their efforts. > > CW donesn't so that for most people. > > Bill, W6WRT Tell that to anyone that uses Aurora! What is that intenmittant buzz on my radio?? Why can't I figure out where this interference is comming from? Can I get my power company to eliminate it? And, by the very nature of it, digital wont decode it (too much distortion). Oh, well! And, BTW,1) The First Class Phone is no longer issued (only General), and 2), the ONLY people NEEDING one is for Marine , and for Airlines! These havent been required for two way, nor broadcast services for years, now! The only reason for the requirement for those two services, are because of International Treaty! Jim NN7K Article: 227230 of rec.radio.amateur.antenna From: "an_old_friend" Subject: Re: Choices, Choices, Choices... CW or CB? Date: 26 Jul 2006 17:12:30 -0700 Message-ID: <1153959150.278310.323390@p79g2000cwp.googlegroups.com> References: Jim - NN7K wrote: > an old friend wrote: > > Jim - NN7K wrote: > > > >>>Laziness is not the issue. It's a question of results gained for the > >>>effort expended. Nearly everyone will put a LOT of effort into > >>>something if they perceive a useful return on their efforts. > >>> > >>>CW donesn't so that for most people. > >>> > >>>Bill, W6WRT > >> > >>Tell that to anyone that uses Aurora! > > > > funny i do some aurora e and i never use cw > > > Then, youi have better announciation, andtonal > understanding than I have! indeed it is a chalange but I am almost as talented verbaly as I impaired in text I have couple of Aurar E over the pol in the FSU and they are not entirely in english either Article: 227231 of rec.radio.amateur.antenna From: "Bob" References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> Subject: Re: neighborhood antenna restrictions Date: Wed, 26 Jul 2006 21:06:50 -0400 Message-ID: <1153962517.218150@www.vif.com> Do you have licence? If yes, you are legall, put antenna up!!!!! Dont listen this all b. s. wrote in message news:1153692686.342597.27820@h48g2000cwc.googlegroups.com... > Help. I've been licensed since 1967, but I haven't been active for > about 20 years. I just bought a FT-101EE with a Cushcraft R4 vertical > antenna, however there are restrictions in my subdivision about > antennas. I'm thinking my best bet may be a long wire between my house > and a neighbor's tree with a tuner. I know this is an ago old battle, > any ideas for an inconspicuous HF antenna? > Article: 227232 of rec.radio.amateur.antenna From: "TF3KX" Subject: High voltage switch/relays for antenna? Date: 26 Jul 2006 18:31:53 -0700 Message-ID: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> Hello: I am contemplating constructing an antenna where a center-fed HALF WAVE will be bent in a loop, only to be isolated at the almost-touching ends by a relay or some other means of a remotely controlled switch. When the relay contacts are open I will have very high RF voltages between the contacts, probably "a few KV" or even more. Are there any suggestions on where I could find a relay, if any, for this? Or any other means for doing this? An additional constraint is that the switching device needs to be light and small (say, 1-2 oz or 20-50 grams). Some ideas I have come up with are: - A small vacuum relay (supplier, type?). - A home-made relay, providing more contact spacing than usually available. - A DC-motor (toy-type) driven mechanism to open and close contacts. - A mercury switch that could be tilted to make or break the contacts. - A string-operated switch to open and close the contacts (would run up the antenna mast). Any comments or suggestions? 73 - Kristinn, TF3KX Article: 227233 of rec.radio.amateur.antenna From: w8ji@akorn.net Subject: Re: High voltage switch/relays for antenna? Date: 26 Jul 2006 18:45:11 -0700 Message-ID: <1153964711.173287.205290@m73g2000cwd.googlegroups.com> References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> TF3KX wrote: > Any comments or suggestions? I assume you are going to switch the loop for lowest band into a bent dipole, and close the relay on higher bands. You might consider a trap, because a relay would have to be very special at any power level. You are deealing with much more than twice the voltage at the ends of a normal dipole from contact to contact. I think your only hope for a relay is a high voltage vacuum relay with wide terminal spacing and good coil insulation. One of the large high voltage glass vacuum relays would be best. It might be possible to build a trap and adjust antenna length so it would work, but the trap would have to be very special in construction. It may not be practical. 73 Tom Article: 227234 of rec.radio.amateur.antenna From: Buck Subject: Re: Does anyone know of any AC (alternating current) 220V or 350V Shortwave Antenna circuits? Message-ID: <7i8gc2pvpgoga5d8n60jt28ck7d73e6rng@4ax.com> References: <1152992924.187331.312250@i42g2000cwa.googlegroups.com> <12bnls86c2ci3f5@corp.supernews.com> <0vrnb29675p1mcgqgdeljvbbbkji3vkbhl@4ax.com> Date: Wed, 26 Jul 2006 22:21:18 -0400 The first BCB shortwave radio station I remember hearing was also HCJB. Grandmother listened to it and netherlands antilles every day. She bought the radio when I was about 7 or so and I helped her unpack it. She showed me about where to find the station. I tuned it until I hear "To God Be The Glory, Great Things He Has Done" tune and it constantly repeat. She was awful proud of me. I listened to it for years. I haven't listened to sw bc much in quite a while. My 706 MKII should do well, but for some reason, I guess I just don't. Buck N4pgw On Tue, 25 Jul 2006 23:56:18 -0000, "Bowser" wrote: >My very first short wave experience ever was listening to HCJB on a 6 >transistor BCB radio when I was 10 years old...I tweaked the tuning cap to >get the thing as far as possible out of the broadcast band range and the >overload from the rural above-ground telephone lines did the rest. Got me >started thinking that there just might be radios in other countries, hi hi. > > >"Buck" wrote in message >news:0vrnb29675p1mcgqgdeljvbbbkji3vkbhl@4ax.com... >> On Mon, 17 Jul 2006 18:31:36 -0000, dplatt@radagast.org (Dave Platt) >> wrote: >> >> >In article , >> >Buck wrote: >> > >> >>There used to be radio antennas that plugged into the wall outlets. >> >>They had a three pronged connector, but only one side was actually >> >>electrically connected, the other prongs were plastic. I am not sure >> >>what they did to isolate the electrical from the radio, but the >> >>antenna used the house wiring for an antenna extension. >> >> >> >>This may be what he is looking for, something that coupled with the >> >>electrical wires for a longer antenna. >> > >> >Ugh. Those things. "Turn your entire house into a gigantic >> >television antenna!" >> > >> >These devices usually just couple one of the wires in the outlet to >> >the antenna lead, using a small high-voltage capacitor. Component >> >parts cost was a few cents, plus the cost of the plug, and (usually) >> >some intricately-shaped plastic case meant to make the device look >> >sophisticated. The case probably cost more than the guts, and the >> >advertised price was far greater than either. >> > >> >From all I've heard, they generally gave poor performance for at least >> >two reasons: >> > >> >- A house's power wiring is an excellent vehicle for RF noise and >> > hash... harmonics from power-supply rectifier, broadband impulse >> > noise from any AC motor with brushes, and so forth. Result: lots >> > of static in the picture. >> > >> >- Multipath. The house wiring is of a complex shape, much larger >> > than a typical TV antenna. The TV or radio signal is likely to be >> > picked up by several different portions of the wiring, which will >> > mix (with varying amounts of time delay) at the coupler. Result: >> > a ghosty picture. >> > >> >To paraphrase a Monty Python sketch concerning a particular Australian >> >table wine: "This is not a technology for using. This is a >> >technology for laying down and avoiding." >> >> >> That sounds like what I was describing. I had an experience once >> where there was a drop cord hanging in a loop shape from a power line >> that lit up a boat pier about 100 feet long or so. When I put my >> shortwave radio near it, I had tremendous reception on MW or SW. I >> didn't need to even use the antenna on the radio. I figure there was >> about 300 total feet of wire the way it was run. Had a great night >> fishing and listening to SWB. >> >> Buck >> -- >> 73 for now >> Buck >> N4PGW > -- 73 for now Buck N4PGW Article: 227235 of rec.radio.amateur.antenna From: Buck Subject: Re: neighborhood antenna restrictions Message-ID: <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> Date: Wed, 26 Jul 2006 22:23:22 -0400 Siding works too. :) depending on if it's grounded or not. I think my strangest antenna was when I connected wires from my tuner to each of the two window screens in the corner room. I worked california from Georgia on 10 meters. :) Buck N4PGW On Wed, 26 Jul 2006 15:02:25 -0400, "Howard W3CQH" wrote: >Be sure that the Gutters are not grounded. If you have Aluminum Siding, the >gutters maybe attached to the siding. A quick check with an ohmmeter should >verify that. >Other wise the gutters make a great antenna. > >"Rayburn" wrote in message >news:e204b$44c6a6ab$8b371d4a$30394@ALLTEL.NET... >> Copper and aluminum Gutters work great!...If they only run across the >> front and back of the house you can connect them with a small wire across >> the roof to make for a nice long antenna! >> >> For example I'm hooked to the bottom of a downspout near the ground on my >> 3 story home....about 28 feet up the guttering starts and runs 25 feet >> across the back of the house......I connected a wire across the roof (60 >> feet long) to the end of the front gutter thats the same height and >> length. >> >> 166 feet of antenna in the shape of an upside down U ! >> >> I buried a couple of ground radials next to a fence for 160...80....40 and >> added a few short ones for 20 /15 and 10 about an inch deep in the >> yard.....works great with a tuner and is fantastic on the L and AM bands >> for reception as well! >> >> Other than a small 4 inch length of coax behind the house next to the >> garage door.....Its invisible! >> wrote in message >> news:1153692686.342597.27820@h48g2000cwc.googlegroups.com... >>> Help. I've been licensed since 1967, but I haven't been active for >>> about 20 years. I just bought a FT-101EE with a Cushcraft R4 vertical >>> antenna, however there are restrictions in my subdivision about >>> antennas. I'm thinking my best bet may be a long wire between my house >>> and a neighbor's tree with a tuner. I know this is an ago old battle, >>> any ideas for an inconspicuous HF antenna? >>> >> >> > -- 73 for now Buck N4PGW Article: 227236 of rec.radio.amateur.antenna From: Buck Subject: Re: Gem Quad Message-ID: References: <2arec29sf7s6801tct4r766ujfppffg4ru@4ax.com> Date: Wed, 26 Jul 2006 22:30:23 -0400 On Wed, 26 Jul 2006 14:27:27 +0100, mike wrote: >Hi >Would anyone using a 2 or 3 element Gem Quad >please get in touch to compare notes. >Thanks >de Mike G4KHG >mikeg4khb@btinternet.com http://www.eham.net/reviews/detail/513 -- 73 for now Buck N4PGW Article: 227237 of rec.radio.amateur.antenna From: ml Subject: batter question Message-ID: Date: Thu, 27 Jul 2006 02:38:49 GMT ok this isn't exactly a antenna question but hope it's ok I have a super powergate ... and a 8g27 gel battery i got a battery from a friend a smaller 25am battery , cant figure out the chemestry but seems like agm so the battery is smaller sized, and perhaps/probably different type(not gel ) i therefore presumed i couldn't parrallel them as they would get different charge rates and poof but someone said that it's ok and each battery will just draw what it needs as it's resistance changes (presuming that both batteries were at equal Volts when i hook them up initially to avoid bat a charging bat b but unsure and feel i should double check a 8g27 blowing up in the house wouldn't be fun thanks Article: 227238 of rec.radio.amateur.antenna From: "Brian 2W0BDW" References: Subject: Re: batter question Message-ID: Date: Thu, 27 Jul 2006 03:33:56 GMT "ml" wrote in message news:m-8C7C2A.22384526072006@news.verizon.net... > ok this isn't exactly a antenna question but hope it's ok > > I have a super powergate ... and a 8g27 gel battery > > i got a battery from a friend a smaller 25am battery , cant figure out > the chemestry but seems like agm > > so the battery is smaller sized, and perhaps/probably different type(not > gel ) > > i therefore presumed i couldn't parrallel them as they would get > different charge rates and poof > > but someone said that it's ok and each battery will just draw what it > needs as it's resistance changes (presuming that both batteries were > at equal Volts when i hook them up initially to avoid bat a charging bat > b > > > but unsure and feel i should double check a 8g27 blowing up in the > house wouldn't be fun > > > thanks If you are unsure then fit a diode on the + terminal of each battery ( one that can handle the current you are going to draw ) with the cathode away >from the battery and connect the cathode ends of the diodes together, take your power from this point. Hey presto the batteries will 'ignore' each other. If you are going to charge them together you can do the same on the + lead of the charger, this time the cathode goes to the battery and the anode goes to the charger. I used to parallel NiCads like this before hi capacity NiMhs came on the market. (NiCad batteries do NOT like to be parallel connected at all!) Hope this helps Brian Article: 227239 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Choices, Choices, Choices... CW or CB? Date: Wed, 26 Jul 2006 21:31:02 -0700 Message-ID: References: <1153847537.309493.36530@b28g2000cwb.googlegroups.com> <1153852119.194366.137430@b28g2000cwb.googlegroups.com> <4iqcc2l2lqa7fg1mahoma3afors04qm8r8@4ax.com> <1153855387.106686.133430@b28g2000cwb.googlegroups.com> <44C670A6.43A73803@milestones.com> <6ebfc2plbt9ov3o11b2ua1d7cnplitn9jk@4ax.com> ORIGINAL MESSAGE: On Wed, 26 Jul 2006 22:35:00 GMT, Jim - NN7K wrote: >Tell that to anyone that uses Aurora! ------------ REPLY SEPARATOR ------------ Yawn. Bill, W6WRT Article: 227240 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: neighborhood antenna restrictions Date: Wed, 26 Jul 2006 21:34:49 -0700 Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> ORIGINAL MESSAGE: On Wed, 26 Jul 2006 22:23:22 -0400, Buck wrote: >I think my strangest antenna was when I connected wires from my tuner >to each of the two window screens in the corner room. I worked >california from Georgia on 10 meters. :) ------------ REPLY SEPARATOR ------------ My strangest was a six meter dipole buried about a foot underground. I worked one station about ten miles away. About a week later I received my WAE award. (Worked All Earthworms). Bill, W6WRT Article: 227241 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Date: Thu, 27 Jul 2006 05:30:37 +0100 Message-ID: "Frank's" wrote > Reg, with the antenna we have established as our test model: > All wires #14, monopole 9 m, 36 X 10m radials 25 mm below > ground. Ground parameters Er = 16, resistivity 150 ohm-m. > I have calculated the radiation efficiency including the surface > wave. What is interesting is that the surface wave contributes > very little at elevation angles over 10 degrees. > > For 100 W input the total radiated power, not considering > the surface wave, is 31 W. When the surface wave is > included the total radiated power is 36 W. > ========================================== Frank, So the missing 64 watts, if not dissipated in the radials must be dissipated in the soil under the antenna. To prove something, what is the efficiency when the ground is sea water. Resistivity = 0.22 ohm-metres and permittivity = 80. PLEASE CONFIRM THE NUMBER OF RADIALS. I thought you were unable to model 36 radials. Were you using only 1 radial? With only 1 radial my program makes efficiency = 28 percent. Which would be satisfactory agreement with your 36 % ) Or did you substitute the radial system with a lumped resistance of 5 ohms which I suggested could be used when estimating efficiency? ---- Reg. Article: 227242 of rec.radio.amateur.antenna From: "Tom Donaly" Subject: Re: Radiating Efficiency References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Message-ID: Date: Thu, 27 Jul 2006 04:36:30 GMT Frank's wrote: >>>The surface or ground wave is the most important fraction of total >>>radiated power. The correct radiation pattern of a vertical antenna >>>shows maximum radiation along the ground. Angle of maximum radiation = >>>0 degrees. >>> >>>When deducing efficiency, to omit power radiated along the ground from >>>the hemispherical integration will result in serious error. >>> >>>( Efficiency by NEC4 ) / ( Efficiency by formula ) = 0.38 >>> >>>I can imagine other losses in addition to loss in the radials but to >>>have the other losses several times greater is a bit much. Where are >>>these large losses? Are they in the soil surface - the only other >>>candidate? >>>---- >>>Reg. >> >>Correct Reg, I had thought the modified RP card >>considered ground wave, but it does not. I am working >>on a combined integration including the surface wave, >>which should provide a more accurate indication of >>the overall efficiency. I will also attempt the >>analysis of various lengths of radial wires. >> >>Frank > > > Reg, with the antenna we have established as our test model: > All wires #14, monopole 9 m, 36 X 10m radials 25 mm below > ground. Ground parameters Er = 16, resistivity 150 ohm-m. > I have calculated the radiation efficiency including the surface > wave. What is interesting is that the surface wave contributes > very little at elevation angles over 10 degrees. > > For 100 W input the total radiated power, not considering > the surface wave, is 31 W. When the surface wave is > included the total radiated power is 36 W. > > Frank > > Good. Now all you have to do is verify your calculations experimentally. 73, Tom Donaly, KA6RUH Article: 227243 of rec.radio.amateur.antenna From: Hans Remeeus Subject: Re: High voltage switch/relays for antenna? Date: Thu, 27 Jul 2006 06:58:35 +0200 Message-ID: <4iqvfsF4tu08U1@individual.net> References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> TF3KX schreef: > Hello: > > I am contemplating constructing an antenna where a center-fed HALF WAVE > will be bent in a loop, only to be isolated at the almost-touching ends > by a relay or some other means of a remotely controlled switch. When > the relay contacts are open I will have very high RF voltages between > the contacts, probably "a few KV" or even more. Are there any > suggestions on where I could find a relay, if any, for this? Or any > other means for doing this? An additional constraint is that the > switching device needs to be light and small (say, 1-2 oz or 20-50 > grams). Some ideas I have come up with are: > > - A small vacuum relay (supplier, type?). > - A home-made relay, providing more contact spacing than usually > available. > - A DC-motor (toy-type) driven mechanism to open and close contacts. > - A mercury switch that could be tilted to make or break the contacts. > - A string-operated switch to open and close the contacts (would run up > the antenna mast). > > Any comments or suggestions? > > 73 - Kristinn, TF3KX > IMHO two high power relays would be an option, about 10 inches seperated >from each other. For example Titanex (www.titanex.de) sells good High Power Ceramics Relais for this purpose: http://www.titanex.de/frames/acc.html#UB6-9 (HPRL) with power handling of 5 kW each. Palstar in the US use high power relais in some of theire antenna tuners, but those relays are not ceramic. Good luck! -- 73, Hans Remeeus (PA1HR) http://www.remeeus.eu Communication is about people, the rest is technology. Article: 227244 of rec.radio.amateur.antenna From: Mike Subject: grounding question Date: Thu, 27 Jul 2006 01:25:29 -0400 Message-ID: I have a discone antenna on my roof and the mast is grounded to the earth with #8 solid wire with a ground rod. I want to use lmr-400 wire for app 50 ft to the scanner. Is it necessary to install the cable with an in-line arrestor ? I hate to have to add more connectors if it isnt necessary...I always unplug the scanner from my cable, rg-58, when Im not using it.....Any thoughts.....Thanks Mike Article: 227245 of rec.radio.amateur.antenna From: Mike Subject: grounding question Date: Thu, 27 Jul 2006 01:27:33 -0400 Message-ID: <9ljgc2hebuutjsp9edm60eckcimlpp7578@4ax.com> I have a discone antenna on my roof and the mast is grounded to the earth with #8 solid wire with a ground rod. I want to use lmr-400 wire for app 50 ft to the scanner. Is it necessary to install the cable with an in-line arrestor ? I hate to have to add more connectors if it isnt necessary...I always unplug the scanner from my cable, rg-58, when Im not using it.....Any thoughts.....Thanks Mike Article: 227246 of rec.radio.amateur.antenna From: nm5k@wt.net Subject: Re: grounding question Date: 27 Jul 2006 02:37:29 -0700 Message-ID: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> References: Mike wrote: > I have a discone antenna on my roof and the mast is grounded to the > earth with #8 solid wire with a ground rod. > I want to use lmr-400 wire for app 50 ft to the scanner. Is it > necessary to install the cable with an in-line arrestor ? I hate to > have to add more connectors if it isnt necessary...I always unplug the > scanner from my cable, rg-58, when Im not using it.....Any > thoughts.....Thanks Mike Well, it's up to you. An arrester is going to be safer than no arrester, but if you are unplugging, maybe you don't need it . But even then, that depends if you actually throw the coax outside when not in use. If you do, maybe you can get by, assuming you never forget to unplug. But if you are just unplugging and leaving it in the room, I'd for sure have an arrester. You do not want an unprotected direct path to the house interior.. No bueno! I don't use arresters, but I'm cheap, and I always ground the unused coax's *outside* to a strip of grounded SO-239's. My mast is grounded well also. I've taken two direct strikes that I'm aware of, and have had no damage at all to anything. Most goes to ground at the mast, and whatever is left on the feedlines goes to ground at the window ground. Both grounds are tied together and are the same appx potential. Some energy does go to ground at the window. I can hear it arc on mast strikes, or sometimes even close indirect strikes. You wouldn't really want that in the house with you unprotected. MK Article: 227247 of rec.radio.amateur.antenna From: Buck Subject: Re: neighborhood antenna restrictions Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> Date: Thu, 27 Jul 2006 05:43:25 -0400 On Wed, 26 Jul 2006 21:34:49 -0700, Bill Turner wrote: >ORIGINAL MESSAGE: > >On Wed, 26 Jul 2006 22:23:22 -0400, Buck wrote: > > >>I think my strangest antenna was when I connected wires from my tuner >>to each of the two window screens in the corner room. I worked >>california from Georgia on 10 meters. :) > >------------ REPLY SEPARATOR ------------ > >My strangest was a six meter dipole buried about a foot underground. I >worked one station about ten miles away. > >About a week later I received my WAE award. (Worked All Earthworms). > >Bill, W6WRT How did you wind up with a dipole buried underground? Were you trying to make a resonant dummy load? -- 73 for now Buck N4PGW Article: 227248 of rec.radio.amateur.antenna From: nm5k@wt.net Subject: Re: High voltage switch/relays for antenna? Date: 27 Jul 2006 02:43:43 -0700 Message-ID: <1153993423.605164.24610@m79g2000cwm.googlegroups.com> References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> TF3KX wrote: > Hello: > > I am contemplating constructing an antenna where a center-fed HALF WAVE > will be bent in a loop, only to be isolated at the almost-touching ends > by a relay or some other means of a remotely controlled switch. When > the relay contacts are open I will have very high RF voltages between > the contacts, probably "a few KV" or even more. Are there any > suggestions on where I could find a relay, if any, for this? Or any > other means for doing this? An additional constraint is that the > switching device needs to be light and small (say, 1-2 oz or 20-50 > grams). Some ideas I have come up with are: > > - A small vacuum relay (supplier, type?). > - A home-made relay, providing more contact spacing than usually > available. > - A DC-motor (toy-type) driven mechanism to open and close contacts. > - A mercury switch that could be tilted to make or break the contacts. > - A string-operated switch to open and close the contacts (would run up > the antenna mast). > > Any comments or suggestions? > > 73 - Kristinn, TF3KX Dunno.. I used to use 24 volt relays that normally are used for fan motors, etc, but I never fed at a high voltage point. I did run a lot of power though. They always worked fine, but who knows with a real high potential.. Might arc over.. I've heard tell of one kinda weird method that supposably will work. I've never tried it though. You run a line of coax from that open point on the antenna, to the shack, and use a switch on the end of the coax to open and close. Like I say, I've never tried it myself, so it' may or may not work... MK Article: 227249 of rec.radio.amateur.antenna From: Buck Subject: Re: grounding question Message-ID: <6r2hc2p6rp6vko0p0bbi3gr84ug7gf2dmf@4ax.com> References: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> Date: Thu, 27 Jul 2006 05:50:23 -0400 On 27 Jul 2006 02:37:29 -0700, nm5k@wt.net wrote: > >Mike wrote: >> I have a discone antenna on my roof and the mast is grounded to the >> earth with #8 solid wire with a ground rod. >> I want to use lmr-400 wire for app 50 ft to the scanner. Is it >> necessary to install the cable with an in-line arrestor ? I hate to >> have to add more connectors if it isnt necessary...I always unplug the >> scanner from my cable, rg-58, when Im not using it.....Any >> thoughts.....Thanks Mike > >Well, it's up to you. An arrester is going to be safer than >no arrester, but if you are unplugging, maybe you don't need >it . But even then, that depends if you actually throw the coax >outside when not in use. If you do, maybe you can get by, >assuming you never forget to unplug. But if you are just unplugging >and leaving it in the room, I'd for sure have an arrester. >You do not want an unprotected direct path to the house interior.. >No bueno! I don't use arresters, but I'm cheap, and I always >ground the unused coax's *outside* to a strip of grounded SO-239's. >My mast is grounded well also. I've taken two direct strikes that >I'm aware of, and have had no damage at all to anything. Most goes >to ground at the mast, and whatever is left on the feedlines goes to >ground at the window ground. Both grounds are tied together and are >the same appx potential. Some energy does go to ground at the window. >I can hear it arc on mast strikes, or sometimes even close indirect >strikes. >You wouldn't really want that in the house with you unprotected. >MK About three years ago I disconnected my dipole antenna from my IC-706 and tossed the pl-259 connector into my plastic trash can. A little later the power went out and I heard a sizzle. The white trash can was glowing from the arcs going across the connector. It wasn't bright, but in the dark it was noticeable. There wasn't any lightning or thunder at that time. It really got me to thinking about what the radio would be like if i had left it plugged in. I unplug my rigs much more often now. Buck n4pgw -- 73 for now Buck N4PGW Article: 227250 of rec.radio.amateur.antenna Date: Thu, 27 Jul 2006 10:47:38 +0000 From: Maxwell Smart #99 Subject: No See Um Antennas underground antenna Message-ID: <44c899ce_1@news.iprimus.com.au> See ARRL Antenna Compendium Vol 5 W7JGM, tells of his experiences using a buried long wire antenna. He compared it to high inverted V and he reported that most of the time the signal strength was close to the same. He did report that when the ground got wet his signal dropped. Regardless After reading KM5KG's web page describing buried dipole dummy loads, i will keep my coax and copper in the air! But hey Diamond and Comet sell vertical antennas with resistors in them and users report good results. Performance is indeed in the mind of the user. Pat Article: 227251 of rec.radio.amateur.antenna Date: Thu, 27 Jul 2006 08:20:15 -0400 From: Dave Subject: Re: neighborhood antenna restrictions References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <1153962517.218150@www.vif.com> Message-ID: Bob wrote: > Do you have licence? If yes, you are legall, put antenna up!!!!! > Dont listen this all b. s. > > ------ reply separator ------- This is not quite accurate. If he signed a contract, i.e. agreed to a set of CC&Rs in a private subdivision at the time of purchase, he is obliged to honor the contract. Contract law in private, not public, domain trumps PRB-1. ------ reply separator ------- > wrote in message > news:1153692686.342597.27820@h48g2000cwc.googlegroups.com... > >>Help. I've been licensed since 1967, but I haven't been active for >>about 20 years. I just bought a FT-101EE with a Cushcraft R4 vertical >>antenna, however there are restrictions in my subdivision about >>antennas. I'm thinking my best bet may be a long wire between my house >>and a neighbor's tree with a tuner. I know this is an ago old battle, >>any ideas for an inconspicuous HF antenna? >> > > > Article: 227252 of rec.radio.amateur.antenna From: "Frank" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Message-ID: Date: Thu, 27 Jul 2006 12:37:45 GMT >> Reg, with the antenna we have established as our test model: >> All wires #14, monopole 9 m, 36 X 10m radials 25 mm below >> ground. Ground parameters Er = 16, resistivity 150 ohm-m. >> I have calculated the radiation efficiency including the surface >> wave. What is interesting is that the surface wave contributes >> very little at elevation angles over 10 degrees. >> >> For 100 W input the total radiated power, not considering >> the surface wave, is 31 W. When the surface wave is >> included the total radiated power is 36 W. >> >> Frank > > Good. Now all you have to do is verify your calculations > experimentally. > 73, > Tom Donaly, KA6RUH You got that right. I need a serious VNA so bad, I can taste it! 73, Frank Article: 227253 of rec.radio.amateur.antenna From: w8ji@akorn.net Subject: Re: Radiating Efficiency Date: 27 Jul 2006 06:16:56 -0700 Message-ID: <1154006216.466440.165890@p79g2000cwp.googlegroups.com> References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> Tom Donaly wrote: > Frank's wrote: > >>>The surface or ground wave is the most important fraction of total > >>>radiated power. The correct radiation pattern of a vertical antenna > >>>shows maximum radiation along the ground. Angle of maximum radiation = > >>>0 degrees. > >>> > >>>When deducing efficiency, to omit power radiated along the ground from > >>>the hemispherical integration will result in serious error. > >>> > >>>( Efficiency by NEC4 ) / ( Efficiency by formula ) = 0.38 > >>> > >>>I can imagine other losses in addition to loss in the radials but to > >>>have the other losses several times greater is a bit much. Where are > >>>these large losses? Are they in the soil surface - the only other > >>>candidate? > >>>---- > >>>Reg. > >> > >>Correct Reg, I had thought the modified RP card > >>considered ground wave, but it does not. I am working > >>on a combined integration including the surface wave, > >>which should provide a more accurate indication of > >>the overall efficiency. I will also attempt the > >>analysis of various lengths of radial wires. > >> > >>Frank > > > > > > Reg, with the antenna we have established as our test model: > > All wires #14, monopole 9 m, 36 X 10m radials 25 mm below > > ground. Ground parameters Er = 16, resistivity 150 ohm-m. > > I have calculated the radiation efficiency including the surface > > wave. What is interesting is that the surface wave contributes > > very little at elevation angles over 10 degrees. > > > > For 100 W input the total radiated power, not considering > > the surface wave, is 31 W. When the surface wave is > > included the total radiated power is 36 W. > > > > Frank > > > > > > Good. Now all you have to do is verify your calculations > experimentally. > 73, > Tom Donaly, KA6RUH That's right. Without verification by direct measurements any program like this is guesswork. 73 Tom Article: 227254 of rec.radio.amateur.antenna From: kb9rqz_child_molester@yahoo.com Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 27 Jul 2006 06:24:09 -0700 Message-ID: <1154006649.105747.75520@h48g2000cwc.googlegroups.com> References: <1152976976.776663.120710@m79g2000cwm.googlegroups.com> an old freind wrote: > peewee_lloyd_davies@yahoo.com wrote: > may the lord bless and keep you and grant you peace Poor spamming Markie! Article: 227255 of rec.radio.amateur.antenna From: kb9rqz_child_molester@yahoo.com Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 27 Jul 2006 06:25:51 -0700 Message-ID: <1154006751.917686.135600@m73g2000cwd.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> an old friend wrote: > kb9rqz_child_molester@yahoo.com wrote: > > > May you die in a horrible accident because of brake failure. > you are truly a sicko But you are the one who molests kids. Article: 227256 of rec.radio.amateur.antenna From: w8ji@akorn.net Subject: Re: High voltage switch/relays for antenna? Date: 27 Jul 2006 06:30:53 -0700 Message-ID: <1154007053.497255.229600@i42g2000cwa.googlegroups.com> References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> Hans Remeeus wrote: > For example Titanex (www.titanex.de) sells good High Power Ceramics > Relais for this purpose: > http://www.titanex.de/frames/acc.html#UB6-9 (HPRL) with power handling > of 5 kW each. > > Palstar in the US use high power relais in some of theire antenna > tuners, but those relays are not ceramic. > > Good luck! I would say good luck also if I assumed a relay could actually be rated for a certain number of "kW". A relay that easily takes 50kW in a 50 ohm system could fail at 100 watts in an application like this, so it is foolish to even look at power ratings in other applications. In this case when the relay is open he will have very high voltages across the contacts even with very modest power. When the relay is closed he will have a few amps of current at low power up to 5 or 10 amps at kilowatt levels. Not only will he have high voltage between contacts, he will have high voltages from the contact to ground. That virtually excludes conventional relays, and it even excludes many types of vacuum relays. The popular ceramic vacuum relays normally have too low of coil to contact breakdown plus the terninal spacing is much less than 1/2 inch. He probably can get by with a conventional ceramic vacuum relay like an RJ1A (about $50 US surplus) at low power levels (normally considered a "5kW relay, whatever that means) , but if he runs more than a few hundred watts and especially if there is moisture in the air he will need a HV glass vacuum with opposing terminals for contacts and a long insulation bar on the transfer solenoid bar. Power levels depend on the application, and he has picked about the toughest application I can think of. 73 Tom Article: 227257 of rec.radio.amateur.antenna From: "w8ji@akorn.net" Subject: Heliax Help Needed Date: 27 Jul 2006 06:39:12 -0700 Message-ID: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> I have some aluminum 50 ohm Heliax I need connectors for, but the part number is worn off the cable. It is 7/8th inch. It is copper clad aluminum solid center conductor. The shield is a lightly heliax ribbed aluminum shield. It's a quality cable so I hate to toss it, and no...even though I have a lathe I don't want to make conectors. It is going on a big tower and I can't risk having connectors fail, so I need the proper connectors. Does this cable sound like anything anyone knows about? Thanks, Tom Article: 227258 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: neighborhood antenna restrictions Date: Thu, 27 Jul 2006 07:22:45 -0700 Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> ORIGINAL MESSAGE: On Thu, 27 Jul 2006 05:43:25 -0400, Buck wrote: >How did you wind up with a dipole buried underground? Were you trying >to make a resonant dummy load? > ------------ REPLY SEPARATOR ------------ There was an article in QST about underground antennas. It might have been an April fool's article but it was so long ago I don't remember for sure. I was 14 or 15 and anything seemed possible. :-) Years later I came to the conclusion that I worked the other guy with incidental radiation from the rig itself and/or the coax feedline, not the antenna itself. Bill, W6WRT Article: 227259 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: High voltage switch/relays for antenna? References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> <4iqvfsF4tu08U1@individual.net> <1154007053.497255.229600@i42g2000cwa.googlegroups.com> Message-ID: <7I4yg.12614$2v.11400@newssvr25.news.prodigy.net> Date: Thu, 27 Jul 2006 15:10:59 GMT w8ji@akorn.net wrote: > In this case when the relay is open he will have very high voltages > across the contacts even with very modest power. When the relay is > closed he will have a few amps of current at low power up to 5 or 10 > amps at kilowatt levels. I performed this same function in Arizona with a $5 relay. There is a surplus store beside the freeway in South Phoenix. They carry surplus relays from the local power company. Some of those relays are high voltage rated. I choose a SPST relay that had four contacts. Two contacts were about an inch apart and, when energized, were shorted by an insulated shorting bar. When not energized, there was a total of at least one inch of air gap in the contact path, maybe more. The contacts were about 1/4" in diameter. I was running 100 watts. I borrowed a differential high voltage scope and measured the peak to peak voltage between the ends of my loop to be somewhat less than ~2500 volts. This was a full wave 40m loop broken in the middle and tuned to resonance on 80m. I tested it in increasing increments of 10 watts all the way to 100 watts with no problem. It was before the monsoon season so the humidity was low. A couple of months later, a severe thunderstorm broke my upper 2x2 support and brought the whole thing tumbling down. -- 73, Cecil, http://www.qsl.net/w5dxp Article: 227260 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: neighborhood antenna restrictions References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> Message-ID: Date: Thu, 27 Jul 2006 15:17:53 GMT Bill Turner wrote: > There was an article in QST about underground antennas. It might have > been an April fool's article but it was so long ago I don't remember > for sure. I was 14 or 15 and anything seemed possible. :-) Back in the '50's, Larsen E. Rapp got me with one of those articles. He said we could create an "amplitude discriminator" with "back to back limiters". That way, we could simply discriminate by tuning out the strong signal and tuning in the weak signal. I asked W5OLV how to build back to back limiters. He couldn't stop laughing. -- 73, Cecil, http://www.qsl.net/w5dxp Article: 227261 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 27 Jul 2006 08:23:21 -0700 Message-ID: <1154013801.724582.277530@m79g2000cwm.googlegroups.com> References: <1152976976.776663.120710@m79g2000cwm.googlegroups.com> kb9rqz_child_molester@yahoo.com wrote: may the lord bless and keep you and grant you peace Article: 227262 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 27 Jul 2006 08:23:56 -0700 Message-ID: <1154013836.038127.240080@p79g2000cwp.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> kb9rqz_child_molester@yahoo.com wrote: may the lord bless and keep you and grant you peace Article: 227263 of rec.radio.amateur.antenna From: Win Subject: Re: High voltage switch/relays for antenna? Date: Thu, 27 Jul 2006 11:23:11 -0500 Message-ID: References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> Kristinn, I think I would consider the Jennings RJ1A or the Kilovac HC-1 high speed vacuum relays. I use them in my amp for QSK operation. http://www.mgs4u.com/relay.htm Good luck. Win, W0LZ Article: 227264 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: grounding question Date: Thu, 27 Jul 2006 09:21:41 -0700 Message-ID: References: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> <6r2hc2p6rp6vko0p0bbi3gr84ug7gf2dmf@4ax.com> On Thu, 27 Jul 2006 05:50:23 -0400, Buck wrote: >It really got me to thinking about what the >radio would be like if i had left it plugged in. I unplug my rigs >much more often now. Hi Buck, Did it get you to thinking about how you replaced the path to ground at the time you were unpluggin your rigs? 73's Richard Clark, KB7QHC Article: 227265 of rec.radio.amateur.antenna Subject: Re: Heliax Help Needed From: Ed References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> Message-ID: Date: 27 Jul 2006 16:47:07 GMT > I have some aluminum 50 ohm Heliax I need connectors for, but the part > number is worn off the cable. > > It is 7/8th inch. It is copper clad aluminum solid center conductor. > The shield is a lightly heliax ribbed aluminum shield. It's a quality > cable so I hate to toss it, and no...even though I have a lathe I don't > want to make conectors. It is going on a big tower and I can't risk > having connectors fail, so I need the proper connectors. > > Does this cable sound like anything anyone knows about? Too many types to tell from what you have said. Is it jacketed or is the outer "ribbed" shield bare? Are you sure you can't find ANY numbers or lettering at all on it that might help? Short of cutting off a foot and running it around to various Radio maintenance shops and Cable TV providers, I dont know how to ID unlabeled material. Ed Article: 227266 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: neighborhood antenna restrictions Date: Thu, 27 Jul 2006 12:33:43 -0500 Message-ID: <12chu7kf24achb5@corp.supernews.com> References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> Cecil Moore wrote: > Bill Turner wrote: > >> There was an article in QST about underground antennas. It might have >> been an April fool's article but it was so long ago I don't remember >> for sure. I was 14 or 15 and anything seemed possible. :-) > > > Back in the '50's, Larsen E. Rapp got me with one of those > articles. He said we could create an "amplitude discriminator" > with "back to back limiters". That way, we could simply > discriminate by tuning out the strong signal and tuning > in the weak signal. I asked W5OLV how to build back to > back limiters. He couldn't stop laughing. I still like to think about an article in "Popular Electronics" back in the late 50's or early 60's about "CONTRA POLAR ENERGY". This principal worked in the exact opposite manner to regular energy: electric lamps absorbed light, heaters froze etc. It got me for many years until someone queried PE about it years later. The cat was let out out the bag. To bad it was an interesting concept. Dave N Article: 227267 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Date: Thu, 27 Jul 2006 19:01:14 +0100 Message-ID: Frank, the reason I asked what the efficiency is when using sea water was to prove your own efficiency calculations. With sea water the efficiency should be very near to 100 percent. You get 93% WITHOUT taking the surface wave into account. To make youself happy you could include the surface wave. Program Radial_3, with sea water, makes efficiency 98 percent which I'm confident is near enough correct. Most of the loss is in the HF resistance of the 14-gauge antenna wire. ======================================================== It's beginning to look as though the oft-quoted formula - Efficiency = Rrad / ( Rrad + Rloss ) is very much in error. This formula is quoted in all the ARRL books and other learned magazines. I will correct my program to agree better with NEC4 even though the absolute value of efficiency is not important and is used only as an indication to maximise effectiveness of the radial system. I await your experiments to determine the impedance Zo of ONE radial wire and the approximate distance at which it occurs. You can do N = 36 radials at a later date. Thank you very much. ---- Reg. Article: 227268 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Radiating Efficiency Date: Thu, 27 Jul 2006 11:39:42 -0700 Message-ID: <802ic2dnjhaatmk6o67vlkmtc551ttbcr8@4ax.com> References: <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> On Thu, 27 Jul 2006 19:01:14 +0100, "Reg Edwards" wrote: >It's beginning to look as though the oft-quoted formula - > >Efficiency = Rrad / ( Rrad + Rloss ) > >is very much in error. Hi Reggie, In fact the entire enquiry has justified it. How do you come to the opposite conclusion? 73's Richard Clark, KB7QHC Article: 227269 of rec.radio.amateur.antenna Date: Thu, 27 Jul 2006 14:44:47 -0400 From: jawod Subject: ARRL Antenna Modeling Course Message-ID: Anyone care to share their experience with ARRL's Antenna Modeling Course? Is it worth it? Cost is about $160 for ARRL members (including manual) and requires EZNEC...does it require the ARRL EZNEC or the commercial version? (I don't know.) Thanks in advance for any comments. John AB8WH Article: 227270 of rec.radio.amateur.antenna From: Danny Richardson Subject: Re: ARRL Antenna Modeling Course Date: Thu, 27 Jul 2006 12:59:27 -0700 Message-ID: References: On Thu, 27 Jul 2006 14:44:47 -0400, jawod wrote: > Anyone care to share their experience with ARRL's Antenna Modeling > Course? Is it worth it? Cost is about $160 for ARRL members (including > manual) and requires EZNEC...does it require the ARRL EZNEC or the > commercial version? > (I don't know.) > > Thanks in advance for any comments. > > John > AB8WH You can purchase the course book for around $40.00 USD from the ARRL. Doing that you'll have a good reference book for future use at hand. The book is the complete course word for word and very well written. Plus the money you'll save will pay for EZNEC with a little pocket change left over. Danny K6MHE Article: 227271 of rec.radio.amateur.antenna From: "Ken Finney" Subject: Re: neighborhood antenna restrictions Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <1153962517.218150@www.vif.com> Date: Thu, 27 Jul 2006 19:50:29 GMT "Dave" wrote in message news:ZNydnVz6XLPjMlXZnZ2dnUVZ_qCdnZ2d@comcast.com... > Bob wrote: > >> Do you have licence? If yes, you are legall, put antenna up!!!!! >> Dont listen this all b. s. >> >> > ------ reply separator ------- > > This is not quite accurate. If he signed a contract, i.e. agreed to a set > of CC&Rs in a private subdivision at the time of purchase, he is obliged > to honor the contract. Contract law in private, not public, domain trumps > PRB-1. > > ------ reply separator ------- > >> wrote in message >> news:1153692686.342597.27820@h48g2000cwc.googlegroups.com... >> >>>Help. I've been licensed since 1967, but I haven't been active for >>>about 20 years. I just bought a FT-101EE with a Cushcraft R4 vertical >>>antenna, however there are restrictions in my subdivision about >>>antennas. I'm thinking my best bet may be a long wire between my house >>>and a neighbor's tree with a tuner. I know this is an ago old battle, >>>any ideas for an inconspicuous HF antenna? >>> I believe President Bush just signed a law preventing subdivisions/HOAs from prohibiting flagpoles. Sounds like a flagpole antenna now trumps subdivisions/HOAs! Article: 227272 of rec.radio.amateur.antenna From: "cmdr buzz corey" Subject: Re: You're not a real ham if you if you keep advocating killing the ARS Date: 27 Jul 2006 13:37:26 -0700 Message-ID: <1154032646.393321.252030@i42g2000cwa.googlegroups.com> References: Slow Code wrote: > "an old freind" wrote in > news:1153857412.613487.278630@h48g2000cwc.googlegroups.com: > > > > > cmdr buzz corey wrote: > >> an old idiot wrote: > >> > >> > sure it is a hobby with service related aspects rather the Boy Scouts > >> > are supposed to be > >> > >> Cite one place in part 97, which defines amateur radio, where it is > >> called a hobby. > > red herring alert > > > > Part 97 does not define Ham radio, Part 97 defines the rules > > > > WE define Ham radio > > > And you want ham radio defined like CB. Ten-Four Good-buddy? > > Dumbing things down cheapens it, and destroys others enjoyment. Look at > the childish bullshit you do in RRAP. You and the other rejects drove > everyone away with all your retarded bathroom hummor. > > That's want will happen with on our HF bands, as it sounds more and more > like CB, good hams will give up on it and leave. Many already have. > When people like two-test wogie and an_old_idiot can get a ticket, you can't hold out much hope for ham radio. Article: 227273 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: neighborhood antenna restrictions Date: Thu, 27 Jul 2006 14:11:07 -0700 Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <1153962517.218150@www.vif.com> On Thu, 27 Jul 2006 19:50:29 GMT, "Ken Finney" wrote: >I believe President Bush just signed a law preventing subdivisions/HOAs from >prohibiting flagpoles. Sounds like a flagpole antenna now trumps >subdivisions/HOAs! H. R. 42 One Hundred Ninth Congress of the United States of America AT THE SECOND SESSION Begun and held at the City of Washington on Tuesday, the third day of January, two thousand and six An Act To ensure that the right of an individual to display the flag of the United States on residential property not be abridged. Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, SECTION 1. SHORT TITLE. This Act may be cited as the ``Freedom to Display the American Flag Act of 2005''. SEC. 2. DEFINITIONS. For purposes of this Act-- (1) the term ``flag of the United States'' has the meaning given the term ``flag, standard, colors, or ensign'' under section 3 of title 4, United States Code; (2) the terms ``condominium association'' and ``cooperative association'' have the meanings given such terms under section 604 of Public Law 96399 (15 U.S.C. 3603); (3) the term ``residential real estate management association'' has the meaning given such term under section 528 of the Internal Revenue Code of 1986 (26 U.S.C. 528); and (4) the term ``member''-- (A) as used with respect to a condominium association, means an owner of a condominium unit (as defined under section 604 of Public Law 96399 (15 U.S.C. 3603)) within such association; (B) as used with respect to a cooperative association, means a cooperative unit owner (as defined under section 604 of Public Law 96399 (15 U.S.C. 3603)) within such association; and (C) as used with respect to a residential real estate management association, means an owner of a residential property within a subdivision, development, or similar area subject to any policy or restriction adopted by such associa tion. SEC. 3. RIGHT TO DISPLAY THE FLAG OF THE UNITED STATES. A condominium association, cooperative association, or residential real estate management association may not adopt or enforce any policy, or enter into any agreement, that would restrict or prevent a member of the association from displaying the flag of the United States on residential property within the association with respect to which such member has a separate ownership interest or a right to exclusive possession or use. SEC. 4. LIMITATIONS. H. R. 42--2 Nothing in this Act shall be considered to permit any display or use that is inconsistent with-- (1) any provision of chapter 1 of title 4, United States Code, or any rule or custom pertaining to the proper display or use of the flag of the United States (as established pursuant to such chapter or any otherwise applicable provision of law); or (2) any reasonable restriction pertaining to the time, place, or manner of displaying the flag of the United States necessary to protect a substantial interest of the condominium association, cooperative association, or residential real estate management association. 73's Richard Clark, KB7QHC Article: 227274 of rec.radio.amateur.antenna From: "Frank's" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Message-ID: Date: Thu, 27 Jul 2006 21:19:38 GMT "Reg Edwards" wrote in message news:iemdncjF_bIfnVTZRVnyqQ@bt.com... > Frank, the reason I asked what the efficiency is when using sea water > was to prove your own efficiency calculations. > > With sea water the efficiency should be very near to 100 percent. You > get 93% WITHOUT taking the surface wave into account. To make youself > happy you could include the surface wave. > > Program Radial_3, with sea water, makes efficiency 98 percent which > I'm confident is near enough correct. Most of the loss is in the HF > resistance of the 14-gauge antenna wire. > > ======================================================== > > It's beginning to look as though the oft-quoted formula - > > Efficiency = Rrad / ( Rrad + Rloss ) > > is very much in error. This formula is quoted in all the ARRL books > and other learned magazines. I will correct my program to agree > better with NEC4 even though the absolute value of efficiency is not > important and is used only as an indication to maximise effectiveness > of the radial system. > > I await your experiments to determine the impedance Zo of ONE radial > wire and the approximate distance at which it occurs. > > You can do N = 36 radials at a later date. > Thank you very much. Reg, The efficiency, including the surface wave, is 96%. There is also a 2% copper loss. With perfect conductors the efficiency would then be 98%. All figures from 100 W input. I have not forgotten the single radial computation. Frank Article: 227275 of rec.radio.amateur.antenna From: peewee_lloyd_davies@yahoo.com Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 27 Jul 2006 14:29:19 -0700 Message-ID: <1154035759.726716.324180@s13g2000cwa.googlegroups.com> References: <1153139989.393054.210140@h48g2000cwc.googlegroups.com> an old friend wrote: > may the lord bless and keep you and grant you peace I see you finally spelled "peace" correctly after a week of spamming it misspelled. Article: 227276 of rec.radio.amateur.antenna From: "Antonio Vernucci" Subject: Seeking advice on balun Date: Thu, 27 Jul 2006 23:29:58 +0200 Message-ID: <44c93058$0$15863$4fafbaef@reader2.news.tin.it> At my summer QTH I mounted a simple wire delta loop, that I feed with a = standard 300-home TV ribbon (I prefer symmetrical antennas, as having a = good ground is not always that simple).=20 In the station I have an asymmetrical tuner, so, not to get RF on my = radio, I must use a balun in between the tuner and the 300-ohm ribbon = coming from the antenna. =20 I am not so enthusiast about using a common 1:1 or 4:1 toroidal = transformer, as I am not sure on how those transformers behave across = the very wide impedance range that they see at the ribbon end when = operating 7 through 28 MHz. So, I decided to instead use an RF choke that quenches the common mode = RF. I firstly built a thick ferrite core by taping together five 3/8"OD = ferrite rods, 6-inch long. I then made 10 turns of a very thick = insulated red-black twin lead on it. The turns are widely spaced, so as = to have low capacitance between adjacent turns. The system works fine and gives me no problems, but I would like to hear = some opinions on that approach, as I do not often see it proposed as a = solution for feeding balanced lines. Should I instead wish to try a common toroidal transformer, would you = better use the 1:1 or the 4:1 version? My reasoning is as follows: = unless my delta loop resonates on one of the ham bands, its impedance = will generally be rather high. So, using a 4:1 balun would facilitate = the tuner task. Any comment on that too? Thanks and 73 Tony I0JX - Rome, Italy Article: 227277 of rec.radio.amateur.antenna From: peewee_lloyd_davies@yahoo.com Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 27 Jul 2006 14:34:41 -0700 Message-ID: <1154036081.261593.126620@h48g2000cwc.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> an old friend wrote: > may STFU, spammer. Article: 227278 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 27 Jul 2006 14:35:31 -0700 Message-ID: <1154036131.625901.319770@m79g2000cwm.googlegroups.com> References: <1153139989.393054.210140@h48g2000cwc.googlegroups.com> peewee_lloyd_davies@yahoo.com wrote: may the lord bless and grant you pecae from the mental illness that traps you Article: 227279 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 27 Jul 2006 14:52:56 -0700 Message-ID: <1154037175.947310.229030@h48g2000cwc.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> peewee_lloyd_davies@yahoo.com wrote: may the lord bless and grant you pecae from the mental illness that traps you Article: 227280 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Seeking advice on balun Date: Thu, 27 Jul 2006 15:59:04 -0700 Message-ID: References: <44c93058$0$15863$4fafbaef@reader2.news.tin.it> On Thu, 27 Jul 2006 23:29:58 +0200, "Antonio Vernucci" wrote: >So, I decided to instead use an RF choke that quenches the common mode RF. I firstly built a thick ferrite core by taping together five 3/8"OD ferrite rods, 6-inch long. I then made 10 turns of a very thick insulated red-black twin lead on it. The turns are widely spaced, so as to have low capacitance between adjacent turns. > >The system works fine and gives me no problems, but I would like to hear some opinions on that approach, as I do not often see it proposed as a solution for feeding balanced lines. Hi Tony, Sounds good. The only unknown is the ferrite properties for the range of RF. > >Should I instead wish to try a common toroidal transformer, would you better use the 1:1 or the 4:1 version? My reasoning is as follows: unless my delta loop resonates on one of the ham bands, its impedance will generally be rather high. So, using a 4:1 balun would facilitate the tuner task. Any comment on that too? You can also try putting a 1:1 current BalUn (or choke) on the coax going from your rig to the tuner. However, you do not say you had any problems to begin with. If you are trying to achieve symmetry, you need to be able to measure how close, or how far away you are. If you cannot do this, then you don't know how much improvement you are making. 73's Richard Clark, KB7QHC Article: 227281 of rec.radio.amateur.antenna From: "Tam/WB2TT" References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> Subject: Re: Heliax Help Needed Date: Thu, 27 Jul 2006 19:13:23 -0400 Message-ID: <48mdnWZ0iZ7g1lTZnZ2dnUVZ_sGdnZ2d@comcast.com> wrote in message news:1154007552.690829.219970@b28g2000cwb.googlegroups.com... >I have some aluminum 50 ohm Heliax I need connectors for, but the part > number is worn off the cable. > > It is 7/8th inch. It is copper clad aluminum solid center conductor. > The shield is a lightly heliax ribbed aluminum shield. It's a quality > cable so I hate to toss it, and no...even though I have a lathe I don't > want to make conectors. It is going on a big tower and I can't risk > having connectors fail, so I need the proper connectors. > > Does this cable sound like anything anyone knows about? > > Thanks, Tom > If you go to www.heliax.com, you can see what matches up with what you have. Tam Article: 227282 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Date: Fri, 28 Jul 2006 00:26:39 +0100 Message-ID: Frank, The efficiency formula is incomplete rather than being in error. In the case of radial systems it could be something like - Efficiency = Rr / ( Rr + Rradials + Rsoilsurface ) . When soil resistivity becomes very small, efficiency approaches 100 percent and the error when compared with NEC4 reduces to zero. The error is therefore a function of soil resistivity. ---- Reg. Article: 227283 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Date: Fri, 28 Jul 2006 00:37:02 +0100 Message-ID: <34SdnZXq57ul0lTZRVnyjw@bt.com> > Good. Now all you have to do is verify your calculations > experimentally. > 73, > Tom Donaly, KA6RUH ======================================== When 2 + 3 + 1 = 6 inches, do you always have to verify it with a wooden ruler? ;o) ---- Reg. Article: 227284 of rec.radio.amateur.antenna Date: Thu, 27 Jul 2006 19:55:19 -0400 From: VOA SWLer Subject: ARRL Maryland State Convention this Saturday, July 29, in Hagerstown, Message-ID: ARRL Maryland State Convention this Saturday, July 29, in Hagerstown, MD. For info, click on: Article: 227285 of rec.radio.amateur.antenna From: "Reg Edwards" References: <44c93058$0$15863$4fafbaef@reader2.news.tin.it> Subject: Re: Seeking advice on balun Date: Fri, 28 Jul 2006 00:57:26 +0100 Message-ID: "Antonio Vernucci" wrote So, I decided to instead use an RF choke that quenches the common mode RF. I firstly built a thick ferrite core by taping together five 3/8"OD ferrite rods, 6-inch long. I then made 10 turns of a very thick insulated red-black twin lead on it. The turns are widely spaced, so as to have low capacitance between adjacent turns. ========================================= Congratulations. You have just re-invented the choke balun. It's what many people use. It is the best choice. Very often it is wound on a ferrite ring. It has no impedance or turns ratio. Or it may consist of a number of ferrite sleeves which slide over the transmission line. It is a mistake to use a balun between tuner and transmission line which has a definite impedance or turns ratio. ---- Reg. Article: 227286 of rec.radio.amateur.antenna From: "w8ji@akorn.net" Subject: Re: Heliax Help Needed Date: 27 Jul 2006 17:02:43 -0700 Message-ID: <1154044963.169788.197220@75g2000cwc.googlegroups.com> References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> Ed wrote: > Too many types to tell from what you have said. Is it jacketed or is > the outer "ribbed" shield bare? Are you sure you can't find ANY numbers > or lettering at all on it that might help? Can't find any readable numbers. It is probably older cable, but it is in good shape and hate to toss it. It is 50 ohm. 7/8 inch. Tough thin black jacket, bare aluminum with much smaller ribs than normal Andrews heliax, closed cell foam insulation, copper clad solid core aluminum center conductor. Just thought someone might know. Can't find anything anywhere myself, so I might have to just toss it out. Article: 227287 of rec.radio.amateur.antenna From: "w8ji@akorn.net" Subject: Re: Heliax Help Needed Date: 27 Jul 2006 17:04:16 -0700 Message-ID: <1154045056.359031.68270@i3g2000cwc.googlegroups.com> References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> Tam/WB2TT wrote: > If you go to www.heliax.com, you can see what matches up with what you have. > > Tam Thanks Tam, but no joy. Article: 227288 of rec.radio.amateur.antenna Date: Thu, 27 Jul 2006 20:17:48 -0400 From: Dave Subject: Re: Radiating Efficiency References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Message-ID: <_4KdnchfyenqylTZnZ2dnUVZ_radnZ2d@comcast.com> Reg Edwards wrote: > Frank, > > The efficiency formula is incomplete rather than being in error. > > In the case of radial systems it could be something like - > > Efficiency = Rr / ( Rr + Rradials + Rsoilsurface ) . > > When soil resistivity becomes very small, efficiency approaches 100 > percent and the error when compared with NEC4 reduces to zero. The > error is therefore a function of soil resistivity. > ---- > Reg. > > So, Rloss = Rradials + Rsoilsurface. The components of Rloss change depending on the antenna being studied. But, Efficiency is still % = (Rr/(Rr + Rloss))*100 /s/ DD Article: 227289 of rec.radio.amateur.antenna Subject: Re: Heliax Help Needed From: Ed References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> <1154044963.169788.197220@75g2000cwc.googlegroups.com> Message-ID: Date: 28 Jul 2006 00:35:13 GMT > It is 50 ohm. 7/8 inch. Tough thin black jacket, bare aluminum with > much smaller ribs than normal Andrews heliax, closed cell foam > insulation, copper clad solid core aluminum center conductor. > > Just thought someone might know. Can't find anything anywhere myself, > so I might have to just toss it out. > I'm not familiar with any 50 ohm heliax with non-copper sheild. I am posting your query on another list. We'll see if there are any responses. Ed K7AAT Article: 227290 of rec.radio.amateur.antenna Subject: Re: Heliax Help Needed From: Ed References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> <1154044963.169788.197220@75g2000cwc.googlegroups.com> Message-ID: Date: 28 Jul 2006 00:40:52 GMT > It is 50 ohm. 7/8 inch. Tough thin black jacket, bare aluminum with > much smaller ribs than normal Andrews heliax, closed cell foam > insulation, copper clad solid core aluminum center conductor. > BTW, how do you know its 50 ohm? Every aluminum jacketed heliax I've come across has been 70 ohm, used in the video industry. Ed Article: 227291 of rec.radio.amateur.antenna From: ml Subject: Re: batter question References: Message-ID: Date: Fri, 28 Jul 2006 00:58:24 GMT In article , "Brian 2W0BDW" wrote: > "ml" wrote in message > news:m-8C7C2A.22384526072006@news.verizon.net... > > ok this isn't exactly a antenna question but hope it's ok > > > > I have a super powergate ... and a 8g27 gel battery > > > > i got a battery from a friend a smaller 25am battery , cant figure out > > the chemestry but seems like agm > > > > so the battery is smaller sized, and perhaps/probably different type(not > > gel ) > > > > i therefore presumed i couldn't parrallel them as they would get > > different charge rates and poof > > > > but someone said that it's ok and each battery will just draw what it > > needs as it's resistance changes (presuming that both batteries were > > at equal Volts when i hook them up initially to avoid bat a charging bat > > b > > > > > > but unsure and feel i should double check a 8g27 blowing up in the > > house wouldn't be fun > > > > > > thanks > > If you are unsure then fit a diode on the + terminal of each battery ( one > that can handle the current you are going to draw ) with the cathode away > from the battery and connect the cathode ends of the diodes together, take > your power from this point. > > Hey presto the batteries will 'ignore' each other. > > If you are going to charge them together you can do the same on the + lead > of the charger, this time the cathode goes to the battery and the anode > goes to the charger. > > I used to parallel NiCads like this before hi capacity NiMhs came on the > market. (NiCad batteries do NOT like to be parallel connected at all!) > > Hope this helps > > Brian <<<<><< thanks very much for the help i sorta thought about diodes but figured hen say both bateries are charged or even 1 how would my charger be able to 'sence' this from the batery? and how would it say stop charging bat a but still flow V to the 2nd batt? "if they are parrrallel" so my fear is in charging mode 1 batt might get way overcharged ???? Article: 227292 of rec.radio.amateur.antenna Message-ID: <44C96259.AD167D51@shaw.ca> From: Irv Finkleman Subject: Re: neighborhood antenna restrictions References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> <12chu7kf24achb5@corp.supernews.com> Date: Fri, 28 Jul 2006 01:03:22 GMT "David G. Nagel" wrote: > > I still like to think about an article in "Popular Electronics" back in > the late 50's or early 60's about "CONTRA POLAR ENERGY". This principal > worked in the exact opposite manner to regular energy: electric lamps > absorbed light, heaters froze etc. It got me for many years until > someone queried PE about it years later. The cat was let out out the > bag. To bad it was an interesting concept. > > Dave N It was around 1954 -- I was just getting into electronics and had built my first crystal set! Boy! Was I ever gullible then! Irv VE6BP -------------------------------------- Visit my HomePage at http://members.shaw.ca/finkirv/index.html Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm -------------------- Irv Finkleman, Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP Calgary, Alberta, Canada Article: 227293 of rec.radio.amateur.antenna From: "Jerry Martes" References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> Subject: Re: Heliax Help Needed Message-ID: Date: Fri, 28 Jul 2006 01:08:32 GMT wrote in message news:1154007552.690829.219970@b28g2000cwb.googlegroups.com... >I have some aluminum 50 ohm Heliax I need connectors for, but the part > number is worn off the cable. > > It is 7/8th inch. It is copper clad aluminum solid center conductor. > The shield is a lightly heliax ribbed aluminum shield. It's a quality > cable so I hate to toss it, and no...even though I have a lathe I don't > want to make conectors. It is going on a big tower and I can't risk > having connectors fail, so I need the proper connectors. > > Does this cable sound like anything anyone knows about? > > Thanks, Tom Hi Tom I see some N connectors for 7/8th heliax in eBay right now, Buy It Now $35.00 with free shipping. is there any chance you would want to communicate with the seller?? Jerry Article: 227294 of rec.radio.amateur.antenna From: "Rayburn" References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <12cdr19v6ef346@corp.supernews.com> Subject: Re: neighborhood antenna restrictions Date: Thu, 27 Jul 2006 21:16:29 -0400 Message-ID: <189f7$44c96570$8b370cf3$22716@ALLTEL.NET> This means you can fly a flag ...not put up a 40 foot flagpole. Its still gotta look good in the opinion of the CCR cops. Aint nothing in the legislation says anything about flagpoles! "David G. Nagel" wrote in message news:12cdr19v6ef346@corp.supernews.com... > Rayburn wrote: > >> Copper and aluminum Gutters work great!...If they only run across the >> front and back of the house you can connect them with a small wire across >> the roof to make for a nice long antenna! >> >> For example I'm hooked to the bottom of a downspout near the ground on my >> 3 story home....about 28 feet up the guttering starts and runs 25 feet >> across the back of the house......I connected a wire across the roof (60 >> feet long) to the end of the front gutter thats the same height and >> length. >> >> 166 feet of antenna in the shape of an upside down U ! >> >> I buried a couple of ground radials next to a fence for 160...80....40 >> and added a few short ones for 20 /15 and 10 about an inch deep in the >> yard.....works great with a tuner and is fantastic on the L and AM bands >> for reception as well! >> >> Other than a small 4 inch length of coax behind the house next to the >> garage door.....Its invisible! >> wrote in message >> news:1153692686.342597.27820@h48g2000cwc.googlegroups.com... >> >>>Help. I've been licensed since 1967, but I haven't been active for >>>about 20 years. I just bought a FT-101EE with a Cushcraft R4 vertical >>>antenna, however there are restrictions in my subdivision about >>>antennas. I'm thinking my best bet may be a long wire between my house >>>and a neighbor's tree with a tuner. I know this is an ago old battle, >>>any ideas for an inconspicuous HF antenna? >>> >> >> >> > > > Congress just passed and the President signed a Federal Law that stops the > CC&R cops from prohibiting flying the American Flag on your property. This > means you can have a flag pole (antenna). :) > > Dave WD9BDZ Article: 227295 of rec.radio.amateur.antenna From: "Rayburn" References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <1153962517.218150@www.vif.com> Subject: Re: neighborhood antenna restrictions Date: Thu, 27 Jul 2006 21:24:27 -0400 Message-ID: <2e0ca$44c9674c$8b370cf3$23161@ALLTEL.NET> I dont see the word flagpole anywhere in this legislation...just flag....HOA's can make a law that flags will be on a 4 foot rod if they want....and can even tell you what SIZE flag your allowed! But yea ...you can fly Old Glory! This law really dont help that much. "Richard Clark" wrote in message news:ggaic29soqe6jgm4pueod9e7nhta9a2aj7@4ax.com... > On Thu, 27 Jul 2006 19:50:29 GMT, "Ken Finney" > wrote: > >>I believe President Bush just signed a law preventing subdivisions/HOAs >>from >>prohibiting flagpoles. Sounds like a flagpole antenna now trumps >>subdivisions/HOAs! > > H. R. 42 > > One Hundred Ninth Congress > of the > United States of America > AT THE SECOND SESSION > > Begun and held at the City of Washington on Tuesday, the third day of > January, two thousand and six > > An Act > To ensure that the right of an individual to display the flag of the > United States on residential property not be abridged. > > Be it enacted by the Senate and House of Representatives of the United > States of America in Congress assembled, > > SECTION 1. SHORT TITLE. > This Act may be cited as the ``Freedom to Display the American Flag > Act of 2005''. > > SEC. 2. DEFINITIONS. > For purposes of this Act-- > (1) the term ``flag of the United States'' has the meaning given the > term ``flag, standard, colors, or ensign'' under section 3 of title 4, > United States Code; > (2) the terms ``condominium association'' and ``cooperative > association'' have the meanings given such terms under section 604 of > Public Law 96399 (15 U.S.C. 3603); > (3) the term ``residential real estate management association'' has > the meaning given such term under section 528 of the Internal Revenue > Code of 1986 (26 U.S.C. 528); and > (4) the term ``member''-- > (A) as used with respect to a condominium association, means an > owner of a condominium unit (as defined under section 604 of Public > Law 96399 (15 U.S.C. 3603)) within such association; > (B) as used with respect to a cooperative association, means a > cooperative unit owner (as defined under section 604 of Public Law > 96399 (15 U.S.C. 3603)) within such association; and > (C) as used with respect to a residential real estate management > association, means an owner of a residential property within a > subdivision, development, or similar area subject to any policy or > restriction adopted by such associa tion. > > SEC. 3. RIGHT TO DISPLAY THE FLAG OF THE UNITED STATES. > A condominium association, cooperative association, or residential > real estate management association may not adopt or enforce any > policy, or enter into any agreement, that would restrict or prevent a > member of the association from displaying the flag of the United > States on residential property within the association with respect to > which such member has a separate ownership interest or a right to > exclusive possession or use. > > SEC. 4. LIMITATIONS. H. R. 42--2 > Nothing in this Act shall be considered to permit any display > or use that is inconsistent with-- > (1) any provision of chapter 1 of title 4, United States Code, or any > rule or custom pertaining to the proper display or use of the flag of > the United States (as established pursuant to such chapter or any > otherwise applicable provision of law); > or > (2) any reasonable restriction pertaining to the time, place, or > manner of displaying the flag of the United States necessary to > protect a substantial interest of the condominium association, > cooperative association, or residential real estate management > association. > > > 73's > Richard Clark, KB7QHC Article: 227296 of rec.radio.amateur.antenna From: Jim - NN7K Subject: Re: neighborhood antenna restrictions References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> <12chu7kf24achb5@corp.supernews.com> Message-ID: <96eyg.183010$F_3.61338@newssvr29.news.prodigy.net> Date: Fri, 28 Jul 2006 01:53:09 GMT Dr Shorza Gitchigoomie also wrote about Useing "Negative Resistance" to do the Contra Polar Energy thing. Funny, I could never get these to work the way he described them (think was about 14 at the time)! That was CQ's premier "Engineer"! Jim NN7K > >> Bill Turner wrote: >> >>> There was an article in QST about underground antennas. It might have >>> been an April fool's article but it was so long ago I don't remember >>> for sure. I was 14 or 15 and anything seemed possible. :-) >> >> >> >> Back in the '50's, Larsen E. Rapp got me with one of those >> articles. He said we could create an "amplitude discriminator" >> with "back to back limiters". That way, we could simply >> discriminate by tuning out the strong signal and tuning >> in the weak signal. I asked W5OLV how to build back to >> back limiters. He couldn't stop laughing. > > > > I still like to think about an article in "Popular Electronics" back in > the late 50's or early 60's about "CONTRA POLAR ENERGY". This principal > worked in the exact opposite manner to regular energy: electric lamps > absorbed light, heaters froze etc. It got me for many years until > someone queried PE about it years later. The cat was let out out the > bag. To bad it was an interesting concept. > > Dave N Article: 227297 of rec.radio.amateur.antenna From: Allodoxaphobia Subject: Re: Heliax Help Needed Date: 28 Jul 2006 01:58:03 GMT Message-ID: References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> <1154044963.169788.197220@75g2000cwc.googlegroups.com> On 28 Jul 2006 00:40:52 GMT, Ed wrote: > >> It is 50 ohm. 7/8 inch. Tough thin black jacket, bare aluminum with >> much smaller ribs than normal Andrews heliax, closed cell foam >> insulation, copper clad solid core aluminum center conductor. > > BTW, how do you know its 50 ohm? Every aluminum jacketed heliax I've > come across has been 70 ohm, used in the video industry. That was my think, too. I've worked with both the 1/2 inch and the 3/4 inch cable TV hardline before. But, then, I never worked with the 7/8 inch stuff and I've never seen any cable TV hardline that was "ribbed". Jonesy -- Marvin L Jones | jonz | W3DHJ | linux 38.24N 104.55W | @ config.com | Jonesy | OS/2 *** Killfiling google posts: Article: 227298 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Seeking advice on balun References: <44c93058$0$15863$4fafbaef@reader2.news.tin.it> Message-ID: Date: Fri, 28 Jul 2006 02:26:39 GMT Antonio Vernucci wrote: > My reasoning is as follows: unless my delta loop resonates on one > of the ham bands, its impedance will generally be rather high. So, > using a 4:1 balun would facilitate the tuner task. Any comment on > that too? If the delta loop's impedance is rather high and the feedline is an odd multiple of 1/4 wavelengths, what impedance will the balun see? -- 73, Cecil http://www.qsl.net/w5dxp Article: 227299 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: neighborhood antenna restrictions Date: Thu, 27 Jul 2006 21:40:09 -0500 Message-ID: <12ciu85pgndm7c0@corp.supernews.com> References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> <12chu7kf24achb5@corp.supernews.com> <44C96259.AD167D51@shaw.ca> Irv Finkleman wrote: > "David G. Nagel" wrote: > > >>I still like to think about an article in "Popular Electronics" back in >>the late 50's or early 60's about "CONTRA POLAR ENERGY". This principal >>worked in the exact opposite manner to regular energy: electric lamps >>absorbed light, heaters froze etc. It got me for many years until >>someone queried PE about it years later. The cat was let out out the >>bag. To bad it was an interesting concept. >> >>Dave N > > > It was around 1954 -- I was just getting into electronics and had > built my first crystal set! Boy! Was I ever gullible then! > > Irv VE6BP > > -------------------------------------- > Visit my HomePage at http://members.shaw.ca/finkirv/index.html > Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm > Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm > -------------------- > Irv Finkleman, > Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP > Calgary, Alberta, Canada We should know now what we knew then. HI HI.... Dave Article: 227300 of rec.radio.amateur.antenna From: "Tom Donaly" Subject: Re: Radiating Efficiency References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> <34SdnZXq57ul0lTZRVnyjw@bt.com> Message-ID: Date: Fri, 28 Jul 2006 02:53:30 GMT Reg Edwards wrote: >>Good. Now all you have to do is verify your calculations >>experimentally. >>73, >>Tom Donaly, KA6RUH > > ======================================== > > When 2 + 3 + 1 = 6 inches, do you always have to verify it with a > wooden ruler? ;o) > ---- > Reg. > > 2 + 3 + 1 doesn't ever equal 6 inches. 2 inches + 3 inches + 1 inch does, however, and if you build something that is 2 inches + 3 inches + 1 inch, you'll most likely verify it with a ruler just to see how close you got. 73, Tom Donaly, KA6RUH Article: 227301 of rec.radio.amateur.antenna From: "Tam/WB2TT" References: <1154007552.690829.219970@b28g2000cwb.googlegroups.com> <48mdnWZ0iZ7g1lTZnZ2dnUVZ_sGdnZ2d@comcast.com> <1154045056.359031.68270@i3g2000cwc.googlegroups.com> Subject: Re: Heliax Help Needed Date: Thu, 27 Jul 2006 23:00:37 -0400 Message-ID: <5aadnfyIk6Fa4FTZnZ2dnUVZ_sKdnZ2d@comcast.com> wrote in message news:1154045056.359031.68270@i3g2000cwc.googlegroups.com... > > Tam/WB2TT wrote: >> If you go to www.heliax.com, you can see what matches up with what you >> have. >> >> Tam > > Thanks Tam, but no joy. > Where did you measure the 7/8 ? Only 50 Ohm Heliax I have used was 1/2, but that measures about 5/8 OD. BTW, other than Andrew, Times Microwave also makes cable like that. Can't recall what they call it. Tam Article: 227302 of rec.radio.amateur.antenna From: "palaniappan chellappan" Subject: Reflection on Resistive loads Date: 27 Jul 2006 20:30:57 -0700 Message-ID: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> I am trying to understand forward and reflection power throught practical circuits , instead of going through books. I found forward/reverse power meters measure reverse power by measuring the phase difference between current and voltage at load terminals. If current and voltage are in phase, there is no reflection . am i correct ? if it is correct , if transmitter has 50+j0 ohm output impedance , and if i connect antenna tuned to 100+j0 ohm. (assume no long cable is used , directly connected ) , reverse power is zero ? regards, palani Article: 227303 of rec.radio.amateur.antenna From: "Sal M. Onella" Subject: Capacitive Hat Message-ID: Date: Thu, 27 Jul 2006 21:43:15 -0700 I know a capacitive hat (or capacitance hat) lowers the resonant frequency of a whip by electrically lengthening it, but by how much? When I was in the service, one of our techs loaded an AFRTS BCB transmitter (1520 kHz, I think) into a 35-foot whip that had a capacitive hat. The hat was a five foot diameter ring of #10 wire with four spokes off the top of the whip. I don't recall (or never knew) what other matching he did. 50 watts went about ten miles, so it worked OK, not great. The ARRL antenna book makes it look like the physical length is about 2/3 of the electrical length (60 degrees physical length plus 30 degrees from the hat). Article: 227304 of rec.radio.amateur.antenna From: Mike Subject: Re: grounding question Date: Fri, 28 Jul 2006 01:43:53 -0400 Message-ID: References: On Thu, 27 Jul 2006 01:25:29 -0400, Mike wrote: >I have a discone antenna on my roof and the mast is grounded to the >earth with #8 solid wire with a ground rod. >I want to use lmr-400 wire for app 50 ft to the scanner. Is it >necessary to install the cable with an in-line arrestor ? I hate to >have to add more connectors if it isnt necessary...I always unplug the >scanner from my cable, rg-58, when Im not using it.....Any >thoughts.....Thanks Mike Thanks for all the responses....Mike Article: 227305 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Capacitive Hat Date: Thu, 27 Jul 2006 23:32:40 -0700 Message-ID: References: On Thu, 27 Jul 2006 21:43:15 -0700, "Sal M. Onella" wrote: >I know a capacitive hat (or capacitance hat) lowers the resonant frequency >of a whip by electrically lengthening it, but by how much? Hi OM, The hat replaces roughly double its length in height - or so goes one proportions of one magic formula. So, for your example of: >a 35-foot whip that had a capacitive hat. The hat was a five >foot diameter ring of #10 wire with four spokes off the top of the whip. hat would say it is equivalent to a 40 foot radiator (35 + 2 · 2.5). I've often wondered why anyone would go to the trouble to wrestle with the mechanical details of keeping a top hat aloft, when they couldn't manage what would be 5 additional feet of whip in this case. Top hats built out of guys is another story, but free-standing hats seems more like adornment than being necessity driven. You may note this doesn't come even remotely close to resonant for 1520 KHz - if that was the implication in your posting. Further, it would be an amazing top hat that could for a 35 foot whip. 73's Richard Clark, KB7QHC Article: 227306 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Reflection on Resistive loads Date: Thu, 27 Jul 2006 23:39:26 -0700 Message-ID: References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> On 27 Jul 2006 20:30:57 -0700, "palaniappan chellappan" wrote: > >I am trying to understand forward and reflection power >throught practical circuits , instead of going through books. Hi Palani, The remainder of your post suggests you should go through the books. > >I found forward/reverse power meters measure reverse >power by measuring the phase difference between current >and voltage at load terminals. WRONG. However, what you say is right by parts. They measure voltage, they measure current, and they measure differences, but not in the simple manner you describe. The sum of the parts does not equal the total of the statement. >If current and voltage >are in phase, there is no reflection . am i correct ? WRONG. See following: > >if it is correct , >if transmitter has 50+j0 ohm output impedance , and if i connect >antenna tuned to 100+j0 ohm. (assume no long cable is used , >directly connected ) , reverse power is zero ? 12% of the power is reflected with a 2:1 (100:50) mismatch, not zero. Current and voltage are in phase (resistive load by your definition of 100+j0 ohm). 73's Richard Clark, KB7QHC Article: 227307 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: neighborhood antenna restrictions Date: Thu, 27 Jul 2006 23:52:38 -0700 Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <1153962517.218150@www.vif.com> <2e0ca$44c9674c$8b370cf3$23161@ALLTEL.NET> On Thu, 27 Jul 2006 21:24:27 -0400, "Rayburn" wrote: >I dont see the word flagpole anywhere in this legislation...just >flag....HOA's can make a law that flags will be on a 4 foot rod if they >want....and can even tell you what SIZE flag your allowed! Hi OM, Quite true. >But yea ...you can fly Old Glory! And I've seen how abysmally our flag is treated by far too many suburban patriots. Some literally torn to shreds on flagpoles, others faded with age, yet more as dirty as diapers. Far too many flown at night. The flag has become more a soiled bib announcing a tailgate picnic than a matter of pride. >This law really dont help that much. Consider the source, how many of our "legislator's" have actually stood in arms under that flag? Half their constituency would be behind bars for desecration if the current laws were enforced. 73's Richard Clark, KB7QHC (having served in many color guards) Article: 227308 of rec.radio.amateur.antenna From: Buck Subject: Re: grounding question Message-ID: References: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> <6r2hc2p6rp6vko0p0bbi3gr84ug7gf2dmf@4ax.com> Date: Fri, 28 Jul 2006 04:17:24 -0400 On Thu, 27 Jul 2006 09:21:41 -0700, Richard Clark wrote: >On Thu, 27 Jul 2006 05:50:23 -0400, Buck wrote: > >>It really got me to thinking about what the >>radio would be like if i had left it plugged in. I unplug my rigs >>much more often now. > >Hi Buck, > >Did it get you to thinking about how you replaced the path to ground >at the time you were unpluggin your rigs? > >73's >Richard Clark, KB7QHC It got me to thinking of putting the end of the wire in a jar, which is what I did. The alternative was to toss it out the window, but that wasn't viable at the time. -- 73 for now Buck N4PGW Article: 227309 of rec.radio.amateur.antenna From: Buck Subject: Re: No See Um Antennas underground antenna Message-ID: References: <44c899ce_1@news.iprimus.com.au> Date: Fri, 28 Jul 2006 04:18:49 -0400 On Thu, 27 Jul 2006 10:47:38 +0000, Maxwell Smart #99 wrote: >See ARRL Antenna Compendium Vol 5 > >W7JGM, tells of his experiences using a buried long wire antenna. He >compared it to high inverted V and he reported that most of the time >the signal strength was close to the same. He did report that when the >ground got wet his signal dropped. > >Regardless > >After reading KM5KG's web page describing buried dipole dummy loads, i >will keep my coax and copper in the air! But hey Diamond and Comet sell >vertical antennas with resistors in them and users report good results. >Performance is indeed in the mind of the user. > >Pat There is a 'grasswire' antenna. It is basically a wire run on the ground. Not great but does claim to have low angle radiation. Buck N4pgw -- 73 for now Buck N4PGW Article: 227310 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Reflection on Resistive loads References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> Message-ID: <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> Date: Fri, 28 Jul 2006 11:56:51 GMT palaniappan chellappan wrote: > If current and voltage > are in phase, there is no reflection . am i correct ? No. Assuming Z0 is purely resistive, here's what it takes to make your statement true: If current and voltage are in phase *at every point* up and down a transmission line, there is no reflection. Just to be sure we have cause and effect straight, the statement should probably be: Assuming the presence of a signal, if there are no reflections on a purely resistive Z0 transmission line, the current and voltage will be in phase at every point on the transmission line. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227311 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Capacitive Hat References: Message-ID: Date: Fri, 28 Jul 2006 12:01:41 GMT Sal M. Onella wrote: > I know a capacitive hat (or capacitance hat) lowers the resonant frequency > of a whip by electrically lengthening it, but by how much? What I do to answer questions like that for myself is to model the antenna system using EZNEC. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227312 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: neighborhood antenna restrictions References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <1153962517.218150@www.vif.com> <2e0ca$44c9674c$8b370cf3$23161@ALLTEL.NET> Message-ID: Date: Fri, 28 Jul 2006 12:05:04 GMT Richard Clark wrote: > Consider the source, how many of our "legislator's" have actually > stood in arms under that flag? Half their constituency would be > behind bars for desecration if the current laws were enforced. If the current laws were enforced, half the legislators would be behind bars. :-) -- 73, Cecil http://www.qsl.net/w5dxp Article: 227313 of rec.radio.amateur.antenna From: John Ferrell Subject: Re: ARRL Antenna Modeling Course Message-ID: References: Date: Fri, 28 Jul 2006 12:10:23 GMT I took the course and purchased the EZNEC + v4.0. For me it was the right way to go. Having the pressure and responsibility of completing the course kept me on topic in a timely fashion. I continue to use the reference material and the program. The EZNEC program allows you to compare a lot of different conditions without expending unnecessary resources. John W8CCW On Thu, 27 Jul 2006 14:44:47 -0400, jawod wrote: >Anyone care to share their experience with ARRL's Antenna Modeling >Course? Is it worth it? Cost is about $160 for ARRL members (including >manual) and requires EZNEC...does it require the ARRL EZNEC or the >commercial version? >(I don't know.) > >Thanks in advance for any comments. > >John >AB8WH John Ferrell W8CCW Article: 227314 of rec.radio.amateur.antenna From: "Not Cocksucker Lloyd" Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 28 Jul 2006 06:04:34 -0700 Message-ID: <1154091874.258246.269450@i3g2000cwc.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> an old freind wrote: >may May you drink some gasoline. Article: 227315 of rec.radio.amateur.antenna From: "Not Cocksucker Lloyd" Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 28 Jul 2006 06:11:16 -0700 Message-ID: <1154092276.631492.304720@i3g2000cwc.googlegroups.com> References: <1153222719.097047.12500@s13g2000cwa.googlegroups.com> an old friend wrote: > may the lord bless and grant you pecae from the mental illness that > traps you ZZZZZZZZZZZZZZZZZZZ! Article: 227316 of rec.radio.amateur.antenna From: "Reg Edwards" References: Subject: Re: Capacitive Hat Date: Fri, 28 Jul 2006 14:26:38 +0100 Message-ID: Sal, A capacitance hat allows you to drive your car into the garage without breaking off a whip of 15 feet equivalent height. A capacitance hat loads a short vertical without suffering the loss in a loading coil. To calculate capacitance of a hat, above an antenna of given height, with N spokes of given length, surrounded by a halo, plus resonant frequency, download program TOPHAT from website below. The program also calculates L and C values of the tuner. The whole job can be done in a couple of minutes. ----- ........................................................... Regards from Reg, G4FGQ For Free Radio Design Software go to http://www.btinternet.com/~g4fgq.regp ........................................................... Article: 227317 of rec.radio.amateur.antenna From: "Reg Edwards" References: Subject: Re: Capacitive Hat Date: Fri, 28 Jul 2006 14:37:39 +0100 Message-ID: Sorry! The correct name of the program is TOPHAT2. ---- > ........................................................... > Regards from Reg, G4FGQ > For Free Radio Design Software go to > http://www.btinternet.com/~g4fgq.regp > ........................................................... > > > Article: 227318 of rec.radio.amateur.antenna From: "the Fords" References: <_KSdnVbqJ9Ykb1vZnZ2dnUVZ_omdnZ2d@giganews.com> Subject: Re: Icom 746PRO Message-ID: Date: Fri, 28 Jul 2006 10:24:33 -0500 Have had one for a year. It is a great rig. Works great on all modes including RTTY and PSK-31. The programming is very human-friendly and the internal ATU works great. The soft key menu system is very intuitive. You won't have to get the manual out very often. -- James Ford K5ACO Article: 227319 of rec.radio.amateur.antenna From: caheaton@netzero.net Subject: base loading vertical with roller inductor? Date: 28 Jul 2006 08:30:43 -0700 Message-ID: <1154100643.691199.3530@b28g2000cwb.googlegroups.com> Hello, I have a vertical antenna that is tuned via taps on a coil at the base. As I was moving the tap the other day I had the idea...why not replace the tapped coil with a roller inductor? This would certainly make tuning easier and as long as the roller is protected >from the elements should work as good as a fixed coil. Is there any reason why this wouldnt' work? Has anybody else modified or built an antenna using such a system? (For the record, the antenna is a Hy-Gain AV18VS. I used to use it only on the low bands and as such rarely had to move the tap, but now that I have an amp and this is the only antenna I have that can handle power, I've been using it more often and on more bands). 73, Craig KB8FGC Article: 227320 of rec.radio.amateur.antenna From: brettsbignose@hotmail.com Subject: Antenna suggestion Date: 28 Jul 2006 10:01:29 -0700 Message-ID: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Sirs: I am a programmer and electrician, but not a radio person! I am sending an experimental balloon to over 100,000 ft. I have purchased two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of 1000 m.a., which states it will transmit and receive up to 20 miles line of sight. I do realize that this is probably under ideal circumstances and will not likely be the case when I actually deploy. I would be interested in purchasing some antennas which would somehow increase the range. What sort of characteristics make up a good antenna for what I want to do? It is possible that someone could find me one that would work with my project? Also, anything you might contribute concerning radio transmission would be very much appreciated. Money is no object for this experiment, so any ideas you have are very much welcome. Thanks, Brett Article: 227321 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 28 Jul 2006 10:30:30 -0700 Message-ID: <1154107830.024254.102600@m73g2000cwd.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> Not Cocksucker Lloyd wrote: > an old freind wrote: > >may > > May you drink some gasoline. you are a sick fuck Article: 227322 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 28 Jul 2006 10:37:02 -0700 Message-ID: <1154108222.365798.120950@i42g2000cwa.googlegroups.com> References: <1153222719.097047.12500@s13g2000cwa.googlegroups.com> Not Cocksucker Lloyd wrote: bearing false witness is a sin wismen Article: 227323 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Subject: Re: Antenna suggestion Date: Fri, 28 Jul 2006 19:13:16 +0100 Message-ID: > Money is no object for this experiment, so any ideas you have are very > much welcome. > > Thanks, > Brett ====================================== Dear Brett, Just send me $800,000 US dollars and I will become your technical adviser for life. Of course, I shall need time-off to spend it. ---- Reg. Article: 227324 of rec.radio.amateur.antenna From: kb9rqz_child_molester@yahoo.com Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 28 Jul 2006 11:55:10 -0700 Message-ID: <1154112910.403538.272330@75g2000cwc.googlegroups.com> References: <1153256502.857930.147640@75g2000cwc.googlegroups.com> an old friend wrote: > bearing false witness is a sin wismen Why do you do it so much? Article: 227325 of rec.radio.amateur.antenna From: Me Subject: Re: neighborhood antenna restrictions References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <1153962517.218150@www.vif.com> <2e0ca$44c9674c$8b370cf3$23161@ALLTEL.NET> Message-ID: Date: Fri, 28 Jul 2006 18:57:46 GMT In article , Cecil Moore wrote: > Richard Clark wrote: > > Consider the source, how many of our "legislator's" have actually > > stood in arms under that flag? Half their constituency would be > > behind bars for desecration if the current laws were enforced. > > If the current laws were enforced, half the legislators > would be behind bars. :-) If current Laws we enforced, half the population would be behind bars, and the other half would be guarding them........... Me Article: 227326 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Date: Fri, 28 Jul 2006 19:57:18 +0100 Message-ID: Frank, I am not interested is what happens at very short lengths or what Radial_3 makes of it. To determine Zo, start around 10 metres. If very little happens to input impedance between 10 and and 15 metres then you already have Zo = Zin = Ro + jXo. Neither am I interested in efficiency or antenna input impedance.. The problem of Efficiency has already been sorted out. All I wish to know is Zin = Zo of a single radial, at various lengths greater than about 10 metres, of diameter = 1.64mm, depth = 25mm, ground resistivity = 150 ohm-metres, permittivity = 16, at a frequency of about 8.07 MHz. That is the input impedance of one radial when the attenuation is about 20dB or greater. To summarise, I wish to know Zo = Ro + jXo for one radial. ---- Reg. Article: 227327 of rec.radio.amateur.antenna From: "Not Cocksucker Lloyd" Subject: Re: may the lord bless and grant you pecae from the mental illness that traps you Date: 28 Jul 2006 12:26:53 -0700 Message-ID: <1154114813.219568.285010@i3g2000cwc.googlegroups.com> References: <1153685459.215393.83880@h48g2000cwc.googlegroups.com> an old friend wrote: > Not Cocksucker Lloyd wrote: > > an old freind wrote: > > >may > > > > May you drink some gasoline. > you are a sick fuck "bearing false witness is a sin" - Morkie Morgan. Marky confirms he married a shemale in <1154036039.815804.294820@p79g2000cwp.googlegroups.com>: "posted you can prove it for yourself anytime you can catch him at home" Article: 227328 of rec.radio.amateur.antenna Message-ID: <44CA686E.A8298473@shaw.ca> From: Irv Finkleman Subject: Re: Antenna suggestion References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Date: Fri, 28 Jul 2006 19:41:32 GMT brettsbignose@hotmail.com wrote: > > Sirs: > > I am a programmer and electrician, but not a radio person! I am > sending an experimental balloon to over 100,000 ft. I have purchased > two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of > 1000 m.a., which states it will transmit and receive up to 20 miles > line of sight. I do realize that this is probably under ideal > circumstances and will not likely be the case when I actually deploy. > I would be interested in purchasing some antennas which would somehow > increase the range. What sort of characteristics make up a good > antenna for what I want to do? It is possible that someone could find > me one that would work with my project? Also, anything you might > contribute concerning radio transmission would be very much > appreciated. > Money is no object for this experiment, so any ideas you have are very > much welcome. > > Thanks, > Brett How about a 100,000 ft trailing wire? Irv VE6BP -------------------------------------- Visit my HomePage at http://members.shaw.ca/finkirv/index.html Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm -------------------- Irv Finkleman, Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP Calgary, Alberta, Canada Article: 227329 of rec.radio.amateur.antenna From: brettsbignose@hotmail.com Subject: Re: Antenna suggestion Date: 28 Jul 2006 12:41:39 -0700 Message-ID: <1154115699.573861.107760@m79g2000cwm.googlegroups.com> References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Is that on Antenna/Radio needs only? :-) Reg Edwards wrote: > > Money is no object for this experiment, so any ideas you have are > very > > much welcome. > > > > Thanks, > > Brett > ====================================== > > Dear Brett, > > Just send me $800,000 US dollars and I will become your technical > adviser for life. Of course, I shall need time-off to spend it. > ---- > Reg. Article: 227330 of rec.radio.amateur.antenna From: "Jerry Martes" References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Subject: Re: Antenna suggestion Message-ID: Date: Fri, 28 Jul 2006 20:09:17 GMT wrote in message news:1154106089.650965.202870@b28g2000cwb.googlegroups.com... > Sirs: > > I am a programmer and electrician, but not a radio person! I am > sending an experimental balloon to over 100,000 ft. I have purchased > two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of > 1000 m.a., which states it will transmit and receive up to 20 miles > line of sight. I do realize that this is probably under ideal > circumstances and will not likely be the case when I actually deploy. > I would be interested in purchasing some antennas which would somehow > increase the range. What sort of characteristics make up a good > antenna for what I want to do? It is possible that someone could find > me one that would work with my project? Also, anything you might > contribute concerning radio transmission would be very much > appreciated. > Money is no object for this experiment, so any ideas you have are very > much welcome. > > Thanks, > Brett Hi Brett . Is it possible that your radio power level is 1,000 m.w. rather than 1000 m.a.? I think this 'antenna' problem can be easily/inexpensively solved. if the location of the balloon is known. Jerry Article: 227331 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Radiating Efficiency Date: 28 Jul 2006 13:26:18 -0700 Message-ID: <1154118378.104563.107880@s13g2000cwa.googlegroups.com> References: <2_OdnX7zdY6gVFzZRVny3w@bt.com> Reg, this whole thread started because bizarre things happen with Radial_3 with short radials. You can go ahead and put a caveat in it if you like, but it's wrong at short lengths and that fact needs to be made clear to users of the program, before they install a radial system of 120 2m radials on 80m and find that it's a terrible ground system. The question that I want answered is how to optimize my radial system, and I think at this point, I shall be consulting a document entitled "Maximum Gain Radial Ground Systems for Vertical Antennas" by K3LC. Anyone have other suggestions for sources of material for optimum radial selection given a certain length of wire? 73, Dan Reg Edwards wrote: > Frank, I am not interested is what happens at very short lengths or > what Radial_3 makes of it. > > To determine Zo, start around 10 metres. > > If very little happens to input impedance between 10 and and 15 metres > then you already have Zo = Zin = Ro + jXo. > > Neither am I interested in efficiency or antenna input impedance.. > The problem of Efficiency has already been sorted out. > etc. Article: 227332 of rec.radio.amateur.antenna From: "Frank's" References: <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> <1154118378.104563.107880@s13g2000cwa.googlegroups.com> Subject: Re: Radiating Efficiency Message-ID: Date: Fri, 28 Jul 2006 20:57:21 GMT > The question that I want answered is how to optimize my radial system, > and I think at this point, I shall be consulting a document entitled > "Maximum Gain Radial Ground Systems for Vertical Antennas" by K3LC. > > Anyone have other suggestions for sources of material for optimum > radial selection given a certain length of wire? > > 73, > Dan Rudy Severns' article; "Verticals, Ground Systems and Some History", in the July 2000 QST, is worth a read. Available on the ARRL web site, or, I also have the pdf. Frank Article: 227333 of rec.radio.amateur.antenna From: "Frank's" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Message-ID: Date: Fri, 28 Jul 2006 21:14:58 GMT > To determine Zo, start around 10 metres. > > If very little happens to input impedance between 10 and and 15 metres > then you already have Zo = Zin = Ro + jXo. > > Neither am I interested in efficiency or antenna input impedance.. > The problem of Efficiency has already been sorted out. > > All I wish to know is Zin = Zo of a single radial, at various lengths > greater than about 10 metres, of diameter = 1.64mm, depth = 25mm, > ground resistivity = 150 ohm-metres, permittivity = 16, at a frequency > of about 8.07 MHz. > > That is the input impedance of one radial when the attenuation is > about 20dB or greater. > > To summarise, I wish to know Zo = Ro + jXo for one radial. Reg, the radial impedance rapidly converges to 101.6 + j 21.1. 10 m -- radial Z = 102 + j 20.99 12 m -- radial Z = 101.3 + j 21.1 14 m -- radial Z = 101.65 + j 21.32 16 m -- radial Z = 101.7 + j 21.1 18 m -- radial Z = 101.615 + j 21.1 20 m -- radial Z = 101.61 + j 21.11 Frank Article: 227334 of rec.radio.amateur.antenna Date: Fri, 28 Jul 2006 17:12:56 -0400 From: john Subject: adaptive beamforming Message-ID: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> I came across a reference about adaptive beamforming in the ARRL Handbook. The reference was from QEX which I don't yet subscribe to. Anyone care to explain/discuss this neat concept? John AB8WH Article: 227335 of rec.radio.amateur.antenna From: "Ralph Mowery" References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Subject: Re: Antenna suggestion Message-ID: Date: Fri, 28 Jul 2006 21:20:43 GMT wrote in message news:1154106089.650965.202870@b28g2000cwb.googlegroups.com... > Sirs: > > I am a programmer and electrician, but not a radio person! I am > sending an experimental balloon to over 100,000 ft. I have purchased > two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of > 1000 m.a., which states it will transmit and receive up to 20 miles > line of sight. I do realize that this is probably under ideal > circumstances and will not likely be the case when I actually deploy. > I would be interested in purchasing some antennas which would somehow > increase the range. What sort of characteristics make up a good > antenna for what I want to do? It is possible that someone could find > me one that would work with my project? Also, anything you might > contribute concerning radio transmission would be very much > appreciated. > Money is no object for this experiment, so any ideas you have are very > much welcome. Just about any antenna will work . I would look into a 1/4 wave antenna mounted upside down so it is pointed down for the balloon. I hope you ment 1,000 mw, or one watt of power for the transmitter. I have heard the hams in the space shuttle and space station with a 5/8 wavelength on my car. They only run a few watts and are over 100 miles up. Also talked with an airplane at 40,000 feet that was over 150 miles away. I was using a 10 watt radio and a small beam. He was using a handy talkey with maybe 5 watts inside the plane. Unless you are under a bunch of trees , there is not much beter conditions than to be line of sight. While it will probably be too small to see without a telescope, as long as the balloon is in sight almost anything will work. Article: 227336 of rec.radio.amateur.antenna From: "Dave" References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> Subject: Re: adaptive beamforming Date: Fri, 28 Jul 2006 21:28:45 -0000 Message-ID: <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> well, 'adaptive beamforming' is two words... 'beamforming' means forming a directional 'beam' using an antenna. be it a simple parasitic array like yagi's or a complex array of driven elements like a flat panel radar. most often when you talk about beamforming it is more like the radar arrays or other large array that combines signals from many small antennas to form a very directional beam. 'adaptive' means forming the beam in a way that makes it work better in the environment, or adapt to it's surroundings. this is often used to form beams to maximize a received signal while notching out interference. so you use an algorithm to measure s/n ratio or some other parameter and adjust power and phasing of the individual elements to get the best signal you can. its harder to adapt a transmitting antenna since you need some kind of feedback from the far end to let you know if the beam is getting better or worse as you adjust it. "john" wrote in message news:383cb$44ca7ea7$d844b81d$19205@FUSE.NET... >I came across a reference about adaptive beamforming in the ARRL Handbook. >The reference was from QEX which I don't yet subscribe to. > > Anyone care to explain/discuss this neat concept? > > John > AB8WH Article: 227337 of rec.radio.amateur.antenna From: "an old freind" Subject: Re: Warning: New Usenet ModeratorTo Shut Down Abusers IfNecesssary. Date: 28 Jul 2006 14:33:54 -0700 Message-ID: <1154122434.436450.145180@m79g2000cwm.googlegroups.com> References: <1153256502.857930.147640@75g2000cwc.googlegroups.com> kb9rqz_child_molester@yahoo.com wrote: > an old friend wrote: > > bearing false witness is a sin wismen > > Why do you do it so much? I don't you do and just did so again Article: 227338 of rec.radio.amateur.antenna From: "JIMMIE" Subject: Re: base loading vertical with roller inductor? Date: 28 Jul 2006 14:39:25 -0700 Message-ID: <1154122765.097433.128370@i3g2000cwc.googlegroups.com> References: <1154100643.691199.3530@b28g2000cwb.googlegroups.com> caheaton@netzero.net wrote: > Hello, I have a vertical antenna that is tuned via taps on a coil at > the base. As I was moving the tap the other day I had the idea...why > not replace the tapped coil with a roller inductor? This would > certainly make tuning easier and as long as the roller is protected > from the elements should work as good as a fixed coil. Is there any > reason why this wouldnt' work? Has anybody else modified or built an > antenna using such a system? (For the record, the antenna is a Hy-Gain > AV18VS. I used to use it only on the low bands and as such rarely had > to move the tap, but now that I have an amp and this is the only > antenna I have that can handle power, I've been using it more often and > on more bands). > 73, Craig KB8FGC Yes it has been done but not without its problems. Stopping the coil in the right place, roller contact with the coil... can all be a problem. I had good luck using a tapped coil and using relays to switch the taps much as is done with an auto tuner. Some radios would allow the coil(s) to be switched automatically with the help of a little extra equipment. Just using manual control is not too bad. I think I saw a circuit to be used with ICOM radio that controls relays by utilizing a DC voltage that changes with band selection/frequecy. This was fed to a group of comparator circiuts that drove the relays. I know of at least one person who has tried this and it proved to be a good route for lightning to get in his radio so my preference is the manual switch controling relays. I dont know how this would work with your radio. The only one I am familar with using this arrangemet was a 30+ ft whip using a big flat metal roof as a couterpoise. Article: 227339 of rec.radio.amateur.antenna From: "an old friend" Subject: bearing false witness is a sin wismen Date: 28 Jul 2006 14:51:57 -0700 Message-ID: <1154123517.528169.9920@h48g2000cwc.googlegroups.com> References: <1153785207.014583.244350@75g2000cwc.googlegroups.com> Not Cocksucker Lloyd wrote: > an old friend wrote: > > Not Cocksucker Lloyd wrote: > > > an old freind wrote: > > > >may > > > > > > May you drink some gasoline. > > you are a sick fuck > > "bearing false witness is a sin" - Morkie Morgan. indeed it is and you have done so wismen in accusing me of child molestaion the wages of sin are DEATH Article: 227340 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: Antenna suggestion Message-ID: References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Date: Fri, 28 Jul 2006 22:29:51 GMT On Fri, 28 Jul 2006 21:20:43 GMT, "Ralph Mowery" wrote: > > wrote in message >news:1154106089.650965.202870@b28g2000cwb.googlegroups.com... >> Sirs: >> >> I am a programmer and electrician, but not a radio person! I am >> sending an experimental balloon to over 100,000 ft. I have purchased >> two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of >> 1000 m.a., which states it will transmit and receive up to 20 miles >> line of sight. I do realize that this is probably under ideal >> circumstances and will not likely be the case when I actually deploy. >> I would be interested in purchasing some antennas which would somehow >> increase the range. What sort of characteristics make up a good >> antenna for what I want to do? It is possible that someone could find >> me one that would work with my project? Also, anything you might >> contribute concerning radio transmission would be very much >> appreciated. >> Money is no object for this experiment, so any ideas you have are very >> much welcome. > >Just about any antenna will work . I would look into a 1/4 wave antenna >mounted upside down so it is pointed down for the balloon. I hope you ment So that would have its pattern null pointed down at the earth? Not to imply that the balloon would necessarily be directly above the observer(s), but if and when it was at the zenith, it would be relatively hard to hear. The OP hasn't told us the elevation angles of the locations of the balloon in flight, how fast it is likely to spin, data rate or equivalent (eg is this intended to send images back?), etc... they are all relevant to commenting on suitability of the 1000mA??? radio, and the type of antennas for the balloon and ground station(s). Owen For an amateur balloon project, see http://members.optusnet.com.au/~philpawlowski/webpages/balloonlaunch1.htm . -- Article: 227341 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: Antenna suggestion Message-ID: References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Date: Fri, 28 Jul 2006 23:01:31 GMT On Fri, 28 Jul 2006 22:29:51 GMT, Owen Duffy wrote: >>> sending an experimental balloon to over 100,000 ft. I have purchased >>> two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of >>> 1000 m.a., which states it will transmit and receive up to 20 miles >>> line of sight. I do realize that this is probably under ideal I did mean to comment on the temperature spec for the radio. The temperature in the troposhere can be as low at -50 to -75 deg C, will the radio get cold enough in transit to fail (eg battery failure, condensation etc). Owen -- Article: 227342 of rec.radio.amateur.antenna Date: Fri, 28 Jul 2006 19:07:45 -0400 From: Dave Subject: Re: Antenna suggestion References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Message-ID: At an altitude of 100,000 feet 1000 mw [1 watt] should reach to the radio horizon of about 300 miles assuming a good receiver on the far end of the range. A vertically polarized 1/2 wavelength antenna should work fine. At least it would be my starting point. Second option would be an inverted [upside down] 1/4 wavelength ground plane. Either antenna is not expensive. What information is to be transmitted? If you are looking for moderate speed telemetry then a path loss versus error rate study needs to be done. If data is being transmitted a gain antenna may be required at the receiver. Gain antennas are not expensive and the antenna needs to be pointed at and follow the balloon's flight path. /s/ DD brettsbignose@hotmail.com wrote: > Sirs: > > I am a programmer and electrician, but not a radio person! I am > sending an experimental balloon to over 100,000 ft. I have purchased > two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of > 1000 m.a., which states it will transmit and receive up to 20 miles > line of sight. I do realize that this is probably under ideal > circumstances and will not likely be the case when I actually deploy. > I would be interested in purchasing some antennas which would somehow > increase the range. What sort of characteristics make up a good > antenna for what I want to do? It is possible that someone could find > me one that would work with my project? Also, anything you might > contribute concerning radio transmission would be very much > appreciated. > Money is no object for this experiment, so any ideas you have are very > much welcome. > > Thanks, > Brett > Article: 227343 of rec.radio.amateur.antenna From: trxggrrw@email.adr Subject: STOP what you’re doing - It doesn’t work! GC83 Message-ID: Date: Fri, 28 Jul 2006 23:54:53 GMT Always staying on the cutting edge of the latest trends and effective advertising methods, Kiosk offers only the best and time worthy promotional tools. If we don't have it, you don't need it! *Supersponder *Prospecting system *Master Profit system *Promotional pages *Complete resell rights for our library of proprietary products *Ad tracking *Membership to our safelist franchise *Super FFA system *Group Networking Click below to find out what has the super-affiliates quaking in their boots http://tinyurl.com/pzkxe Thank you for your time, and we wish you a profitable 2006! Regards, Clive Foster Please visit the following site, for the best promotional and marketing idea we have seen this year: http://tinyurl.com/pzkxe --- Neleh lisero bam cexec lat bisitor begi tamavemif . Article: 227344 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Date: Sat, 29 Jul 2006 03:02:44 +0100 Message-ID: > Reg, the radial impedance rapidly converges to 101.6 + j 21.1. > > 10 m -- radial Z = 102 + j 20.99 > 12 m -- radial Z = 101.3 + j 21.1 > 14 m -- radial Z = 101.65 + j 21.32 > 16 m -- radial Z = 101.7 + j 21.1 > 18 m -- radial Z = 101.615 + j 21.1 > 20 m -- radial Z = 101.61 + j 21.11 > ============================================== Frank, Excellent results! The radial has already converged on Zo = 102 + j21 at a distance of 10 metres. Just where Radial_3 predicts it should. The magnitude of Zo is within 20 percent of NEC4 and the impedance angle is in the right ball-park with the correct sign. Now work downwards from 10 metres, to about 7.5 metres, the 3/4-wave resonant point, to find the point where Zin has truly diverged from Zo. You will have to work in gradually smaller increments. Could you go down to the 1/2-wave resonant point at about 4 metres? You will now be able to see what I'm heading for. By the way, how much hard labour is all this causing you? Don't try to tell me what you are actually doing because I havn't the foggiest idea. ---- Reg, Article: 227345 of rec.radio.amateur.antenna From: "Kryptoknight" Subject: Help with Antenna Message-ID: Date: Sat, 29 Jul 2006 02:13:52 GMT i just picked up a Midland radio 75-822 portable cb. it has the noaa stations too. i am looking for a hi gain ruber ducky bnc antenna. can anyone suggest one? Article: 227346 of rec.radio.amateur.antenna From: Dan Richardson Subject: Re: Help with Antenna Date: Fri, 28 Jul 2006 19:45:43 -0700 Message-ID: <9uilc253cdl0npgtb5ruhn9ongesabv0nk@4ax.com> References: On Sat, 29 Jul 2006 02:13:52 GMT, "Kryptoknight" wrote: >i just picked up a Midland radio 75-822 portable cb. it has the noaa >stations too. i am looking for a hi gain ruber ducky bnc antenna. can anyone >suggest one? A high gain rubber ducky is an oxymoron. > Article: 227347 of rec.radio.amateur.antenna Message-ID: <44CAD516.9050609@fuse.net> Date: Fri, 28 Jul 2006 23:25:10 -0400 From: jawod Subject: Re: adaptive beamforming References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> Dave wrote: > well, 'adaptive beamforming' is two words... > > 'beamforming' means forming a directional 'beam' using an antenna. be it a > simple parasitic array like yagi's or a complex array of driven elements > like a flat panel radar. most often when you talk about beamforming it is > more like the radar arrays or other large array that combines signals from > many small antennas to form a very directional beam. > > 'adaptive' means forming the beam in a way that makes it work better in the > environment, or adapt to it's surroundings. this is often used to form > beams to maximize a received signal while notching out interference. so you > use an algorithm to measure s/n ratio or some other parameter and adjust > power and phasing of the individual elements to get the best signal you can. > its harder to adapt a transmitting antenna since you need some kind of > feedback from the far end to let you know if the beam is getting better or > worse as you adjust it. > > > "john" wrote in message > news:383cb$44ca7ea7$d844b81d$19205@FUSE.NET... > >>I came across a reference about adaptive beamforming in the ARRL Handbook. >>The reference was from QEX which I don't yet subscribe to. >> >>Anyone care to explain/discuss this neat concept? >> >>John >>AB8WH > > > Dave, Thanks for responding. Given the need for "stealth" antennas, Is there /are there design(s) that create small footprint antennas that function as larger traditional ones? Can a longwire be divided into small segments that are independently controlled such that the sum of the parts behave differently than the whole?...and can this effect be altered via software? Has anyone been working on this approach? John AB8WH Article: 227348 of rec.radio.amateur.antenna From: "Bob VK4BYX" Subject: Harris RF-2601 auto remote ATU Date: Sat, 29 Jul 2006 14:15:24 +1000 Message-ID: <44cae0f7$0$23676$5a62ac22@per-qv1-newsreader-01.iinet.net.au> I have the chance to buy a RF-2601 new in its boxes. Can anyone advise me if an RF-2601 and its control unit are a stand alone installation? The data sheet advises it is designed to operate with Harris transmitter. Do they come with an instruction manual? Is further info available? Do you need to pressurise with nitrogen to achieve full specs of 1KW average power? Article: 227349 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Radiating Efficiency Date: Fri, 28 Jul 2006 21:33:36 -0700 Message-ID: <12clp9b5e3ual1c@corp.supernews.com> References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> I've explained this to Reg many times before, but somehow it doesn't seem to sink in. Here's the explanation again. Reg Edwards wrote: > "Frank's" wrote >>>> W7EL tells us that EZNEC doesn't display the surface >>>> wave which obviously contains power. Would that affect >>>> the efficiency using the integration technique? > ====================================== > > The surface or ground wave is the most important fraction of total > radiated power. It's important only to AM broadcasters and others communicating at low frequencies, and to HF operators interested in working distances of only a few miles. At HF, it decays to a negligibly low value within a few miles, and so is no importance at all beyond that distance. > The correct radiation pattern of a vertical antenna > shows maximum radiation along the ground. Angle of maximum radiation = > 0 degrees. Let's consider that for a moment. The surface wave decays rapidly. So the "correct" radiation pattern as described by Reg changes dramatically with distance. At HF, the pattern at one mile will be strikingly different from the pattern at 20 miles; the first will be maximum at zero elevation angle, the latter won't. So if you want this kind of "correct" pattern, you'll have to specify the distance from the antenna. Once you're a few miles away, at HF, the pattern becomes constant with distance, because the surface wave has decayed to essentially zero. Then you have the pattern which is useful in determining communication beyond a few miles. (This is the pattern reported by EZNEC and NEC as the "far field" pattern.) Reg's "correct" pattern isn't useful for anything but short distance communication, and isn't valid except at the distance specified. > When deducing efficiency, to omit power radiated along the ground from > the hemispherical integration will result in serious error. Well, it kind of depends what you lump in with losses when calculating efficiency. The classical formula for antenna efficiency, Rrad/(Rrad + Rloss), generally applies only to the antenna itself and near field losses such as ground system losses. So power in the surface wave is considered to be "radiation", and if you want to calculate this efficiency by dividing the power in the radiated field by the power from the sources, you would have to include the surface wave in the calculation. However, for people communicating more than a few miles, the surface wave power, which is dissipated in the ground within a few miles of the antenna, is just as lost as power dissipated in the wires or the ground system. So if you consider "radiated power" to be power radiated beyond a few miles and "loss" to be the rest, then you can lump the surface wave power into the "loss" portion. If you do that, the efficiency is correctly reported by EZNEC or NEC's average gain function. > ( Efficiency by NEC4 ) / ( Efficiency by formula ) = 0.38 I won't comment on that because I haven't a clue where it came from. > I can imagine other losses in addition to loss in the radials but to > have the other losses several times greater is a bit much. Where are > these large losses? Are they in the soil surface - the only other > candidate? The surface wave power is indeed dissipated in the soil within a few miles of the antenna. Roy Lewallen, W7EL Article: 227350 of rec.radio.amateur.antenna From: "Sal M. Onella" References: <44c07393$0$10058$c3e8da3@news.astraweb.com> Subject: Re: Aluminum tubing for vertical antenna Message-ID: Date: Fri, 28 Jul 2006 21:57:02 -0700 "Hank Zoeller" wrote in message news:44c07393$0$10058$c3e8da3@news.astraweb.com... > Hello everyone, > > I'm contemplating putting up a vertical antenna for HF use. I'm looking > at an approximate height of 30 feet or so. I am thinking of using > aluminum tubing (0.058" wall) in a 'telescoping' manner. Here are my > questions (so far): > > 1) Diameter. For wind resistance, should I start with something like 1 > inch diameter and work down to 3/8 inch? Would the antenna be stronger > if I started with 2 inch diameter and worked down to 1-3/8 inch? > > It would seem to me that the larger diameter might be better able to > withstand wind but it would also offer more resistance to wind possibly > negating the additional strength. But, I have no experience to draw > from. So, fat or slim? > > 2) I am planning a set of guy ropes at about the 12 foot level, a bit > over 1/3 height. Is there a better height for guy ropes? I can put as > much concrete in the ground as I like, and a very robust mount system is > possible. Is there any way to make an unguyed 30 footer that isn't a > tower form factor? Something like making the bottom 12 feet or so from > 2 inch diameter, 1/4 inch wall tubing and then light weight tubing from > there up to full height? > -- > 73, Hank http://www.valcom.ca/Guelph/products/highfreq/as3772b-u_photo.html This is built for navy shipboard use so it may be "scary expensive." These are virtually indestructible. You have to hit one with a crane boom to break it. It is exactly what you described in your last paragraph. This size whip covers 2 - 30 MHz with a tuner. The Navy has used many 35-foot whips over the years. There were five-section versions, but any you found now would probably be too corroded to be of use. Article: 227351 of rec.radio.amateur.antenna From: robert Subject: Re: Question for You Grounding Gurus Date: Sat, 29 Jul 2006 01:51:53 -0400 Message-ID: <12cltrq9a4dhpb4@corp.supernews.com> References: <1153437176.242544.67620@m79g2000cwm.googlegroups.com> Cool - you can cut the rods in half and transport them... since you have four rods, you'll end up with eight equal lengths once cut, of four feet long. There are, however some cons here (I'll get to that). Depending on your local geology and soil content, I would advise checking the conductivity of the soil in the summer, during a dry spell. Depending on the arrangement of the rods, it might also be a good idea to consider a "halo" type ground instead of maybe just sticking them in the ground and then connecting them in parallel - but I'm not sure what your plans are exactly. There are also chemicals which you can use to dope the soil you plan on inserting the rods into... usually an inexpensive ion-rich salt solution, although with such implementation, close attention usually needs to be paid to oxidation / corrosion within the first few years. If water is no object, put in a "soaker system." You can even do this "off the (water) grid" by using a cistern or large water collection reservoir. Overall, I'd say your best bet would be to leave those suckers as long as possible and save yourself the time and headache. Since lightning tends to follow paths of least resistance, avoid sharp turns in your grounding strap or wire - additionally, short rods (depending on their proximity to other grounded equipment) may actually cause the lightning to jump from the incompletely-grounded end of the short rod to the next closest grounded object. I've seen it happen before... if it's close to the surface, it can make for some wild, glassy soil samples. :) And if you can, please use copper strapping, or a GOOD Copper/Nickle braid - several years back (we had never noticed it before), I noticed that the guy cables on our 500' tower were originally grounded using 1/4" copper ground wire - bad idea... every leg was grounded, and the reason we never noticed that they were grounded this way originally???... the ground wire had vaporized and separated into tiny little chunks which ended up scattered in the field... no sign of the wire left at first glance - and the original ground rods were never exposed above soil level. Just in case you might have wondered why braid VS traditional ground wire: electricity travels across the skin of the wire, not so much in the core; more little wires woven together -- more surface area; known as the "skin effect." Although the skin effect is more relevant when dealing with Things like AC or High-Frequency RF, it still applies to the seemingly random actions of lightning. Ok... I'll stop now. Maybe I was able to help with your initial question. sorry about all the fluff. Hope all this helps! Best Wishes and 73's! Jason Stepp KB9TLR - Marion, IN Operations Mgr. WSOT TV "Family Programming you can Trust!" operations@wsot-tv.com Brian Kelly wrote: > I have to transport four U.S. standard 5/8" dia x 8' long ground rods > 35 miles in my four door compact car. Do not want to carry them on the > roof. If I cut them to six feet long I can load them inside the car. > Ignoring any code compliance issues would there be any reason the > shortened rods would not work as well as full-length rods for purposes > of ligtning protection and the usual HF station RF grounding? Soil here > is probably very conductive (damp heavy loam). Thanks. > > Brian w3rv > Article: 227352 of rec.radio.amateur.antenna From: Hans Remeeus Subject: Re: High voltage switch/relays for antenna? Date: Sat, 29 Jul 2006 08:00:38 +0200 Message-ID: <4j0bs6F5n0qsU1@individual.net> References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> <4iqvfsF4tu08U1@individual.net> <1154007053.497255.229600@i42g2000cwa.googlegroups.com> w8ji@akorn.net schreef: > Hans Remeeus wrote: >> For example Titanex (www.titanex.de) sells good High Power Ceramics >> Relais for this purpose: >> http://www.titanex.de/frames/acc.html#UB6-9 (HPRL) with power handling >> of 5 kW each. >> >> Palstar in the US use high power relais in some of theire antenna >> tuners, but those relays are not ceramic. >> >> Good luck! > > > I would say good luck also if I assumed a relay could actually be rated > for a certain number of "kW". > > A relay that easily takes 50kW in a 50 ohm system could fail at 100 > watts in an application like this, so it is foolish to even look at > power ratings in other applications. > > In this case when the relay is open he will have very high voltages > across the contacts even with very modest power. When the relay is > closed he will have a few amps of current at low power up to 5 or 10 > amps at kilowatt levels. > > Not only will he have high voltage between contacts, he will have high > voltages from the contact to ground. > > That virtually excludes conventional relays, and it even excludes many > types of vacuum relays. The popular ceramic vacuum relays normally have > too low of coil to contact breakdown plus the terninal spacing is much > less than 1/2 inch. > > He probably can get by with a conventional ceramic vacuum relay like an > RJ1A (about $50 US surplus) at low power levels (normally considered a > "5kW relay, whatever that means) , but if he runs more than a few > hundred watts and especially if there is moisture in the air he will > need a HV glass vacuum with opposing terminals for contacts and a long > insulation bar on the transfer solenoid bar. > > Power levels depend on the application, and he has picked about the > toughest application I can think of. > > 73 Tom > Hello Tom, I know that, but you forgot to quote an important part of my text: "IMHO two high power relays would be an option, about 10 inches seperated from each other." -- 73, Hans Remeeus (PA1HR) http://www.remeeus.eu Communication is about people, the rest is technology. Article: 227353 of rec.radio.amateur.antenna Date: Sat, 29 Jul 2006 00:16:34 -0600 From: Hank Zoeller Subject: Re: Aluminum tubing for vertical antenna References: <44c07393$0$10058$c3e8da3@news.astraweb.com> Message-ID: <44cafd66$0$1468$c3e8da3@news.astraweb.com> Sal M. Onella wrote: > http://www.valcom.ca/Guelph/products/highfreq/as3772b-u_photo.html This is > built for navy shipboard use so it may be "scary expensive." These are > virtually indestructible. You have to hit one with a crane boom to break > it. It is exactly what you described in your last paragraph. This size > whip covers 2 - 30 MHz with a tuner. > > The Navy has used many 35-foot whips over the years. There were > five-section versions, but any you found now would probably be too corroded > to be of use. Actually, I *did* find one of those things! http://www.american-milspec.com/p961.html Alas, it's a bit too tall for my use. I'm thinking of using a 26' whip with a remote coupler (Harris RF-601) for operating from 40 through 15 meters. Or, I might go to a 30' whip for ops on 60 through 18 meters. I haven't made up my mind yet although I'm leaning toward the 26' version. If I go that route I might pick up a commercial, little brother of that massive Navy style whip - the Shakespeare 5300. It's sold as a 28' whip but it's actually 26' as they use the bottom two feet for a mounting sleeve. It's made for shipboard use but is substantially lighter than the Navy 35' whip. It's only 2-3/8" in diameter, for example.. Time is a precious commodity, at the moment, but I still might roll my own from Texas Towers Aluminum. 73, -- HZ Article: 227354 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <12clp9b5e3ual1c@corp.supernews.com> Subject: Re: Radiating Efficiency Date: Sat, 29 Jul 2006 08:10:13 +0100 Message-ID: Roy, there you go again - confusing the issue by re-stating the bleeding obvious. What happens to the ground wave AFTER it has been radiated is not relevant to the efficiency problem. ( Which has now been sorted out anyway.) The losses we are concerned with all occur in the near field. They are - (A) Loss in the radials and loss in the soil in the vicinity of the radials, which is represented by Rradials. It is the input resistance of the radials. It can be determined by measurements. Rradials is the value used in the usual formula - Efficiency = Rr / ( Rr + Radials ), which, in the present context, is incorrect. (B) Loss in the soil surface and soil NOT in the vicinity of radials, but still in the near field, represented by Rsoil. Frank, using NEC4, has managed to seperate losses A and B although not the resistance of Rsoil. So, after finding a value for Rsoil, a more accurate formula is - Efficiency = Rr / ( Rr + Radials + Rsoil ) Where Rr is the radiation resistance referred to the base of the antenna. Note that Rsoil cannot be measured but can be deduced from the actual efficiency. Both Rradials and Rsoil are functions of the same soil characteristics. ---- Reg, Article: 227355 of rec.radio.amateur.antenna Message-ID: <44CB1EC3.70201@something.com> Date: Sat, 29 Jul 2006 08:39:31 +0000 From: Bitz Subject: Re: Harris RF-2601 auto remote ATU References: <44cae0f7$0$23676$5a62ac22@per-qv1-newsreader-01.iinet.net.au> Bob VK4BYX wrote: > I have the chance to buy a RF-2601 new in its boxes. Can anyone advise me if > an RF-2601 and its control unit are a stand alone installation? The data > sheet advises it is designed to operate with Harris transmitter. Do they > come with an instruction manual? Is further info available? Do you need to > pressurise with nitrogen to achieve full specs of 1KW average power? > > Its Still a supported item by Harris. You can buy all the manuals from them. This coupler is used just about on every Australian and American warships Theres plenty of these tuners on the surplus market. Ontario Surplus sells them and have all the details on them, they dont help customers who dont BUY Harris Stuff from them. Columbia Electronics may also have manuals and information. Murphys surplus in California sells this item. You dont need the "GAS" to obtain the kilowatt rating, that tuner is full of good "stuff" This tuner was mainly designed to be used with a 35ft on a ship. It can run a long wire with some limitations. It probably can take more than a kilowatt, however it depends what kind of antenna you have. I would buy it, and try and complete the complete Harris lineup. This stuff is great, the quality is overwhelming. Good Luck Pat Article: 227356 of rec.radio.amateur.antenna Date: Sat, 29 Jul 2006 08:45:55 +0000 From: Bitz Subject: Re: Aluminum tubing for vertical antenna References: <44c07393$0$10058$c3e8da3@news.astraweb.com> Message-ID: <44cb204f_1@news.iprimus.com.au> Sal M. Onella wrote: > "Hank Zoeller" wrote in message > news:44c07393$0$10058$c3e8da3@news.astraweb.com... >> Hello everyone, >> >> I'm contemplating putting up a vertical antenna for HF use. I'm looking >> at an approximate height of 30 feet or so. I am thinking of using >> aluminum tubing (0.058" wall) in a 'telescoping' manner. Here are my >> questions (so far): >> >> 1) Diameter. For wind resistance, should I start with something like 1 >> inch diameter and work down to 3/8 inch? Would the antenna be stronger >> if I started with 2 inch diameter and worked down to 1-3/8 inch? >> >> It would seem to me that the larger diameter might be better able to >> withstand wind but it would also offer more resistance to wind possibly >> negating the additional strength. But, I have no experience to draw >> from. So, fat or slim? >> >> 2) I am planning a set of guy ropes at about the 12 foot level, a bit >> over 1/3 height. Is there a better height for guy ropes? I can put as >> much concrete in the ground as I like, and a very robust mount system is >> possible. Is there any way to make an unguyed 30 footer that isn't a >> tower form factor? Something like making the bottom 12 feet or so from >> 2 inch diameter, 1/4 inch wall tubing and then light weight tubing from >> there up to full height? >> -- >> 73, Hank > > http://www.valcom.ca/Guelph/products/highfreq/as3772b-u_photo.html This is > built for navy shipboard use so it may be "scary expensive." These are > virtually indestructible. You have to hit one with a crane boom to break > it. It is exactly what you described in your last paragraph. This size > whip covers 2 - 30 MHz with a tuner. > > The Navy has used many 35-foot whips over the years. There were > five-section versions, but any you found now would probably be too corroded > to be of use. > > Just look in the ARRL hanbook and use their 40 meter beam elements. They self supporting and have a wind rating of 90mph. In a vertical configuration with guys they would never blow down in a 100 years. Dont forget the Navy Whips by valcom etc were designed to take a take >from a wave etc. Tons of water would bend any noodle. They really a overkill. Some were also designed to take shock blasts from canons etc and fatigue from 20,000 rounds weakening the metal. Theres a lot of Yagi element stress element software around, i would use it and design it to your spec. I would make sure you use 6061 which is the most corrosion resistant and has the most strength. Array Solutions sells element stress software from some Ham Kurt Andress or something like that. ON4un also has some free software with his latest book. How you gonna tune this beast on all bands? Would be interested to hear how you going about this. Pat Article: 227357 of rec.radio.amateur.antenna Date: Sat, 29 Jul 2006 09:00:17 +0000 From: Bitz Subject: Re: adaptive beamforming References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> <44CAD516.9050609@fuse.net> Message-ID: <44cb23c2_1@news.iprimus.com.au> jawod wrote: > Dave wrote: >> well, 'adaptive beamforming' is two words... >> >> 'beamforming' means forming a directional 'beam' using an antenna. be >> it a simple parasitic array like yagi's or a complex array of driven >> elements like a flat panel radar. most often when you talk about >> beamforming it is more like the radar arrays or other large array that >> combines signals from many small antennas to form a very directional >> beam. >> >> 'adaptive' means forming the beam in a way that makes it work better >> in the environment, or adapt to it's surroundings. this is often used >> to form beams to maximize a received signal while notching out >> interference. so you use an algorithm to measure s/n ratio or some >> other parameter and adjust power and phasing of the individual >> elements to get the best signal you can. its harder to adapt a >> transmitting antenna since you need some kind of feedback from the far >> end to let you know if the beam is getting better or worse as you >> adjust it. >> >> >> "john" wrote in message >> news:383cb$44ca7ea7$d844b81d$19205@FUSE.NET... >> >>> I came across a reference about adaptive beamforming in the ARRL >>> Handbook. The reference was from QEX which I don't yet subscribe to. >>> >>> Anyone care to explain/discuss this neat concept? >>> >>> John >>> AB8WH >> >> >> > Dave, > > Thanks for responding. > > Given the need for "stealth" antennas, Is there /are there design(s) > that create small footprint antennas that function as larger traditional > ones? > > Can a longwire be divided into small segments that are independently > controlled such that the sum of the parts behave differently than the > whole?...and can this effect be altered via software? > > Has anyone been working on this approach? > > John > AB8WH > You can do it with dipoles, like the HAARP transmitter. It has the most gain per acre than any other antenna. You can really use any antennas, just the phasing becomes complicated. You need to ensure all antennas are identical and have the same impedance and reactance etc etc. Its a bloody complicated exercise to design such an array. Look up the varios web pages on google. The DF arrays used around the world are receive only versions of these antennas. Look up "super resolution DF arrays. They amazing stuff! A number of ANtenna companies sell wide band vertical arrays for transmitting. They consist of 12 vertical in a circle with a radiator in the centre. They then have a smaller inner circle for the higher frequencies. I would like to pick up one of the Super DF arrays one day on the surplus market, oh boy what fun you can have! They can work out the location of a station with one DF receiver. Called single station Location. Beam forming on receive and transmit are the same thing in reality. However its not as easy building phase stable antennas on transmit that cover 1.8 to 30 mhz. If you work it all out and can do it for 500 dollars let me know. I would like to buy a beam forming antenna for shortwave receive. With cost of DSP chips dropping who knows maybe some day some smart ham will come up with a Super resolution cheap df system/ beam forming transmit system. Ocean radar also use these complicated systems. HF antennas for all locations RSGB has a article in their for beam forming using compact 1 metre loop antennas, you might want to check it out. Its a homebrew version of the Hermes Loop system. Same thing could be done on transmit with magnetic loops. If you took a ham 8 circle vertical array and substituted magnetic loops you could perhaps do it. You need someone smart like W8JI to figure out all the mathematics and details. Pat Article: 227358 of rec.radio.amateur.antenna From: "w8ji@akorn.net" Subject: Re: High voltage switch/relays for antenna? Date: 29 Jul 2006 03:15:48 -0700 Message-ID: <1154168148.798694.163710@m73g2000cwd.googlegroups.com> References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> Hans Remeeus wrote: > Hello Tom, > > I know that, but you forgot to quote an important part of my text: > > "IMHO two high power relays would be an option, about 10 inches > seperated from each other." That does nothing for breakdown voltages to control cables unless the relays are a certain construction and wired a certain way. It can help with antenna end-to-end breakdown voltage. 73 Tom Article: 227359 of rec.radio.amateur.antenna From: "Dave" References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> <44CAD516.9050609@fuse.net> Subject: Re: adaptive beamforming Date: Sat, 29 Jul 2006 11:00:54 -0000 Message-ID: "jawod" wrote in message news:44CAD516.9050609@fuse.net... > Dave wrote: >> well, 'adaptive beamforming' is two words... >> >> 'beamforming' means forming a directional 'beam' using an antenna. be it >> a simple parasitic array like yagi's or a complex array of driven >> elements like a flat panel radar. most often when you talk about >> beamforming it is more like the radar arrays or other large array that >> combines signals from many small antennas to form a very directional >> beam. >> >> 'adaptive' means forming the beam in a way that makes it work better in >> the environment, or adapt to it's surroundings. this is often used to >> form beams to maximize a received signal while notching out interference. >> so you use an algorithm to measure s/n ratio or some other parameter and >> adjust power and phasing of the individual elements to get the best >> signal you can. its harder to adapt a transmitting antenna since you need >> some kind of feedback from the far end to let you know if the beam is >> getting better or worse as you adjust it. >> >> >> "john" wrote in message >> news:383cb$44ca7ea7$d844b81d$19205@FUSE.NET... >> >>>I came across a reference about adaptive beamforming in the ARRL >>>Handbook. The reference was from QEX which I don't yet subscribe to. >>> >>>Anyone care to explain/discuss this neat concept? >>> >>>John >>>AB8WH >> >> >> > Dave, > > Thanks for responding. > > Given the need for "stealth" antennas, Is there /are there design(s) that > create small footprint antennas that function as larger traditional ones? > > Can a longwire be divided into small segments that are independently > controlled such that the sum of the parts behave differently than the > whole?...and can this effect be altered via software? > > Has anyone been working on this approach? > > John > AB8WH > no, you can't make antennas smaller this way... you can make small parts behave differently, but you can't get more gain or efficiency than a simillarly sized 'normal' antenna. i don't know of any hams actively working in this area, mostly because on hf the antennas get huge quickly. and on vhf/uhf and up there are much simpler ways to get gain for single point to point use that most hams are interested in. the real applications for things like this are radar and multi-point fixed or mobile systems that have to deal with multipath reflection and interference. Article: 227360 of rec.radio.amateur.antenna Date: Sat, 29 Jul 2006 07:44:08 -0400 From: Dave Subject: Re: Antenna suggestion References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Message-ID: <_cSdnaPhdOCa11bZnZ2dnUVZ_vidnZ2d@comcast.com> Owen Duffy wrote: > On Fri, 28 Jul 2006 22:29:51 GMT, Owen Duffy wrote: > > > >>>>sending an experimental balloon to over 100,000 ft. I have purchased >>>>two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of >>>>1000 m.a., which states it will transmit and receive up to 20 miles >>>>line of sight. I do realize that this is probably under ideal > > > I did mean to comment on the temperature spec for the radio. The > temperature in the troposhere can be as low at -50 to -75 deg C, will > the radio get cold enough in transit to fail (eg battery failure, > condensation etc). > > Owen > -- YEP! You have to account for loss of battery power, loss of gain in the semiconductors, etc. Or, provide a stable thermal environment. Article: 227361 of rec.radio.amateur.antenna Date: Sat, 29 Jul 2006 07:46:19 -0400 From: Dave Subject: Re: Help with Antenna References: Message-ID: <_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com> Kryptoknight wrote: > i just picked up a Midland radio 75-822 portable cb. it has the noaa > stations too. i am looking for a hi gain ruber ducky bnc antenna. can anyone > suggest one? > > High gain generally relates to large size. "Rubber Ducky" antennas are low gain compromises. There is no such animal as "High Gain Rubber Ducky" [pun intended] Article: 227362 of rec.radio.amateur.antenna From: "Kryptoknight" References: <_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com> Subject: Re: Help with Antenna Message-ID: <5sIyg.189329$mF2.162247@bgtnsc04-news.ops.worldnet.att.net> Date: Sat, 29 Jul 2006 12:24:33 GMT i know i know. the factory one is a dual band 10" antenna (cb and noaa). i'm looking for the ~27MHz cb band antenna that is approx 12-18" long. this would have better gain than what i have now, but obviously not like a 1/4 or 1/2 wave antenna. any suggestions on through-glass mini "loaded" cb antenna. "Dave" wrote in message news:_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com... > Kryptoknight wrote: > >> i just picked up a Midland radio 75-822 portable cb. it has the noaa >> stations too. i am looking for a hi gain ruber ducky bnc antenna. can >> anyone suggest one? > > High gain generally relates to large size. > > "Rubber Ducky" antennas are low gain compromises. > > There is no such animal as "High Gain Rubber Ducky" [pun intended] > Article: 227363 of rec.radio.amateur.antenna From: "Kryptoknight" References: <_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com> <5sIyg.189329$mF2.162247@bgtnsc04-news.ops.worldnet.att.net> Subject: Re: Help with Antenna Message-ID: Date: Sat, 29 Jul 2006 12:39:38 GMT i know the through-glass antenna suck balls, but i did not want to install a huge whip. i have a 2006 tacoma with tonneau cover. i would do a hard mount on my roof as long as the antenna was one of those thin stainless types. any suggestions (model / part #'s)? thanks "Kryptoknight" wrote in message news:5sIyg.189329$mF2.162247@bgtnsc04-news.ops.worldnet.att.net... >i know i know. the factory one is a dual band 10" antenna (cb and noaa). >i'm looking for the ~27MHz cb band antenna that is approx 12-18" long. this >would have better gain than what i have now, but obviously not like a 1/4 >or 1/2 wave antenna. > > any suggestions on through-glass mini "loaded" cb antenna. > > > "Dave" wrote in message > news:_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com... >> Kryptoknight wrote: >> >>> i just picked up a Midland radio 75-822 portable cb. it has the noaa >>> stations too. i am looking for a hi gain ruber ducky bnc antenna. can >>> anyone suggest one? >> >> High gain generally relates to large size. >> >> "Rubber Ducky" antennas are low gain compromises. >> >> There is no such animal as "High Gain Rubber Ducky" [pun intended] >> > > Article: 227364 of rec.radio.amateur.antenna From: mcalhoun@ksu.edu Subject: Re: Antenna suggestion Date: 29 Jul 2006 08:09:44 -0500 Message-ID: References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> >>>> sending an experimental balloon to over 100,000 ft. I have purchased >>>> two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of >>>> 1000 m.a., which states it will transmit and receive up to 20 miles >>>> line of sight. I do realize that this is probably under ideal >I did mean to comment on the temperature spec for the radio. The >temperature in the troposhere can be as low at -50 to -75 deg C, will >the radio get cold enough in transit to fail (eg battery failure, >condensation etc). You should read Paul Lloyd (Lloyd Paul?) Verhage's long series of "near space" articles which have been running in Nuts & Volts magazine for at least a year! He started sending balloons and packages of scientific experiments (radio telemetry and DF'ing, cameras, once even included some roaches!) into near space years before that. FWIW, he is a "ham", and when he started, he was a student here at Kansas State University. Even better, he launched his balloons >from the "Johnson Near Space Center" about 10 miles south of Manhattan, Kansas; so-called because Dr. Gary Johnson, K0HGJ, who was working to duplicate some of Tesla's high-power experiemts, owned a humongous- big-and-tall metal building with VERY-big sliding doors that was perfect for inflating balloons inside (out of any wind) and carrying outside for launching, and the similarity with the name "Johnson Space Center" was just too good to resist! I believe Lloyd (the name he used then) is now a high-school teacher somewhere, and he incorporates his balloon launches into his science classes. -- --Myron A. Calhoun. Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge NRA Life Member W0PBV "Barbershop" tenor CDL(PTXS) (785) 539-4448 Certified Instructor (KS Concealed Carry, Rifle, Pistol, Home Firearm Safety) Article: 227365 of rec.radio.amateur.antenna From: mcalhoun@ksu.edu Subject: Re: Question for You Grounding Gurus Date: 29 Jul 2006 08:20:01 -0500 Message-ID: References: <1153437176.242544.67620@m79g2000cwm.googlegroups.com> <12cltrq9a4dhpb4@corp.supernews.com> >Cool - you can cut the rods in half and transport them... since you have >four rods, you'll end up with eight equal lengths once cut, of four feet >long. There are, however some cons here (I'll get to that). Depending >on your local geology and soil content, I would advise checking the >conductivity of the soil in the summer, during a dry spell. Depending on >....[snip].... Although I can't cite the reference (I read too many magazines from too many sources), a recent article somewhere gave a fairly-definitive answer regarding grounding vs. depth of ground. Since I don't plan on digging any 35-foot holes (I vaguely recall that number from the article), I didn't even file the article (or if I filed it, I can't find it now!-( -- --Myron A. Calhoun. Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge NRA Life Member W0PBV "Barbershop" tenor CDL(PTXS) (785) 539-4448 Certified Instructor (KS Concealed Carry, Rifle, Pistol, Home Firearm Safety) Article: 227366 of rec.radio.amateur.antenna From: Wes Stewart Subject: Re: adaptive beamforming Date: Sat, 29 Jul 2006 06:28:36 -0700 Message-ID: References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> <44CAD516.9050609@fuse.net> On Sat, 29 Jul 2006 11:00:54 -0000, "Dave" wrote: [snip] >The real applications >for things like this are radar and multi-point fixed or mobile systems that >have to deal with multipath reflection and interference. And things like this: http://www.raytheon.com/products/pgs/index.html#agr Article: 227367 of rec.radio.amateur.antenna Subject: Re: Antenna suggestion From: Dave Oldridge References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Message-ID: Date: Sat, 29 Jul 2006 13:53:11 GMT Owen Duffy wrote in news:i12lc25cteq1dd3pjqqcpr07rtaadnj77k@4ax.com: > On Fri, 28 Jul 2006 21:20:43 GMT, "Ralph Mowery" > wrote: > >> >> wrote in message >>news:1154106089.650965.202870@b28g2000cwb.googlegroups.com... >>> Sirs: >>> >>> I am a programmer and electrician, but not a radio person! I am >>> sending an experimental balloon to over 100,000 ft. I have >>> purchased two 900MHz RF Aerocomm ConnexLink Radios. The radios have >>> a power of 1000 m.a., which states it will transmit and receive up >>> to 20 miles line of sight. I do realize that this is probably under >>> ideal circumstances and will not likely be the case when I actually >>> deploy. I would be interested in purchasing some antennas which >>> would somehow increase the range. What sort of characteristics make >>> up a good antenna for what I want to do? It is possible that >>> someone could find me one that would work with my project? Also, >>> anything you might contribute concerning radio transmission would be >>> very much appreciated. >>> Money is no object for this experiment, so any ideas you have are >>> very much welcome. >> >>Just about any antenna will work . I would look into a 1/4 wave >>antenna mounted upside down so it is pointed down for the balloon. I >>hope you ment > > So that would have its pattern null pointed down at the earth? > > Not to imply that the balloon would necessarily be directly above the > observer(s), but if and when it was at the zenith, it would be > relatively hard to hear. I used to do a lot of radiosonde work. Those balloons would go to 110,000 feet at times. The transmitters were small, probably not more than a watt, but we tracked them with an automatic system. The instrument used a 1680mhz transmitter with an upside-down ground plane antenna in the bottom (I think that was the freq. but it was near there). The tracking antenna, though, was a parabolic dish with a wobbling feed-point antenna that automatically tracked the balloon's radio, giving us a continual readout of azimuth and elevation angles. By combining this data with the received data from the instrument's aneroid barometer, temperature and humidity sensors, we could locate the balloon with good accuracy in three dimensions. Thus the run would provide temperature and humidity profiles as well as data on winds aloft. Balloons almost never go straight over you and when they do it is almost always early in the flight when the signal is close and strong. > The OP hasn't told us the elevation angles of the locations of the > balloon in flight, how fast it is likely to spin, data rate or > equivalent (eg is this intended to send images back?), etc... they are > all relevant to commenting on suitability of the 1000mA??? radio, and > the type of antennas for the balloon and ground station(s). A lot depends on frequency, too. Tracking a 2.4 or 5.8 ghz transmitter is different from tracking a 35mhz transmitter. -- Dave Oldridge+ ICQ 1800667 Article: 227368 of rec.radio.amateur.antenna From: "Michel" Subject: Sperrtopfantenne Date: Sat, 29 Jul 2006 16:27:04 +0200 Message-ID: <44cb703c$0$4516$e4fe514c@news.xs4all.nl> I am looking for a schematic for a homebrew Sperrtopfantenne. I like te construcion pretty much, but I was not able to find construcion plans on the internet. Who helps? Regards, Michel PD1AIW the Netherlands Article: 227369 of rec.radio.amateur.antenna From: Fabian Kurz Subject: Re: Sperrtopfantenne Date: 29 Jul 2006 14:34:14 GMT Message-ID: <4j19v6F5nipuU1@news.dfncis.de> References: <44cb703c$0$4516$e4fe514c@news.xs4all.nl> Michel wrote: > I am looking for a schematic for a homebrew Sperrtopfantenne. I like te > construcion pretty much, but I was not able to find construcion plans on the > internet. Second google hit for "Sperrtopf" brought up this article including construction plans: http://download.antennex.com/hws/ws1002/sperrtopf.pdf 73, -- Fabian Kurz, DJ1YFK * Dresden, Germany * http://fkurz.net/ Online Log: http://dl0tud.tu-dresden.de/~dj1yfk/log.html Article: 227370 of rec.radio.amateur.antenna From: "Michel" References: <44cb703c$0$4516$e4fe514c@news.xs4all.nl> <4j19v6F5nipuU1@news.dfncis.de> Subject: Re: Sperrtopfantenne Date: Sat, 29 Jul 2006 16:51:15 +0200 Message-ID: <44cb75e8$0$4523$e4fe514c@news.xs4all.nl> > > Second google hit for "Sperrtopf" brought up this article > including construction plans: > http://download.antennex.com/hws/ws1002/sperrtopf.pdf > > 73, > -- > Fabian Kurz, DJ1YFK * Dresden, Germany * http://fkurz.net/ > Online Log: http://dl0tud.tu-dresden.de/~dj1yfk/log.html Great... I must be searching with my eyes closed! Article: 227371 of rec.radio.amateur.antenna From: =?ISO-8859-1?Q?Glenn_M=F8ller-Holst?= Subject: Re: adaptive beamforming Date: Sat, 29 Jul 2006 16:59:43 +0200 Message-ID: References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> john wrote: > I came across a reference about adaptive beamforming in the ARRL > Handbook. The reference was from QEX which I don't yet subscribe to. > > Anyone care to explain/discuss this neat concept? > > John > AB8WH Hi John Look at: http://en.wikipedia.org/wiki/Beamforming http://en.wikipedia.org/wiki/Multiple-input_multiple-output http://en.wikipedia.org/wiki/Synthetic_aperture_radar Glenn Article: 227372 of rec.radio.amateur.antenna From: "ZS6AAA" Subject: Re: QST's Louisiana Loop Date: 29 Jul 2006 08:02:29 -0700 Message-ID: <1154185349.636159.106650@75g2000cwc.googlegroups.com> References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> > I am talking about the antenna in this months QST page 38 ZS6AAA > > "The Compact Quad Multiband Hf Antenna" August 2006 > > So i hope i have not crossed wires here. But this antenna is open wire > fed, supported on a single fibreglass pole. > > > Pat Hi Pat Actually the "Compact Quad" is meant to be fed by 50 Ohm coax through a 1:1 balun attached at the end of the open-wire matching section. Here the VSWR should be under 5:1 on the 40, 20, 15 and 10m bands. Of course you can also use open-wire line, but then the VSWR at the radio will depend on the length and characteristic impedance of the feed-line. 73 Andrew ZS6AAA Article: 227373 of rec.radio.amateur.antenna From: =?ISO-8859-1?Q?Glenn_M=F8ller-Holst?= Subject: Re: adaptive beamforming Date: Sat, 29 Jul 2006 17:14:49 +0200 Message-ID: References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> Glenn Mřller-Holst wrote: > john wrote: > >> I came across a reference about adaptive beamforming in the ARRL >> Handbook. The reference was from QEX which I don't yet subscribe to. >> >> Anyone care to explain/discuss this neat concept? >> >> John >> AB8WH > > > Hi John > > Look at: > > http://en.wikipedia.org/wiki/Beamforming > > http://en.wikipedia.org/wiki/Multiple-input_multiple-output > > http://en.wikipedia.org/wiki/Synthetic_aperture_radar > > Glenn Found this illustative article about beamforming: How to create beam-forming smart antennas using FPGAS: http://www.embedded.com/showArticle.jhtml?articleID=60401726 Quote: "...The adaptive process permits narrower beams and reduced output in other directions, significantly improving the signal-to-interference-plus-noise ratio (SINR). With this technology, each user's signal is transmitted and received by the base station only in the direction of that particular user. This drastically reduces the overall interference in the system..." Glenn Article: 227374 of rec.radio.amateur.antenna From: loa210@freemail.gr Subject: broadcast automation software Date: 29 Jul 2006 08:34:38 -0700 Message-ID: <1154187277.964542.223340@s13g2000cwa.googlegroups.com> broadcast automation software --------------------------------------------------- iMediaTouch broadcast automation software, ------------------------------------------------------------ modules m1 ON-AIR module m2 Voice Tracking module m3 Production module m4 LogTools module ------------------------------------------------------------ optional modules om1 RemoteVT ... iMediaTouch Remote VoiceTracking module om2 On-Air Remote ... iMediaTouch On-Air Remote module om3 iMediaDataCast ... RDS Encoder module om4 iMediaLogger ... Digital Logger & Podcaster module om5 iMediaImport ... Automatic Content Importer module om6 iMediaAccess ... Wide Area Content Management module om6 iMediaPix ... Cart Replacement module om7 iMediaMultiStream ... Multi-Channel Live Stream Encoder ------------------------------------------------------------ Article: 227375 of rec.radio.amateur.antenna From: Allodoxaphobia Subject: Re: Sperrtopfantenne Date: 29 Jul 2006 15:37:51 GMT Message-ID: References: <44cb703c$0$4516$e4fe514c@news.xs4all.nl> <4j19v6F5nipuU1@news.dfncis.de> <44cb75e8$0$4523$e4fe514c@news.xs4all.nl> On Sat, 29 Jul 2006 16:51:15 +0200, Michel wrote: > >> >> Second google hit for "Sperrtopf" brought up this article >> including construction plans: >> http://download.antennex.com/hws/ws1002/sperrtopf.pdf >> >> 73, >> -- >> Fabian Kurz, DJ1YFK * Dresden, Germany * http://fkurz.net/ >> Online Log: http://dl0tud.tu-dresden.de/~dj1yfk/log.html > > Great... I must be searching with my eyes closed! I believe I see an error in "Fig. 1" in that document. The text to the left states you need a" Copper pipe with a diameter of 10 mm and a length of 1480 mm". Correct. However, the diagram claims a length of 1480 mm from the top of the antenna to the top of the sleeve. Wrong! That length on the figure should be 975 mm and/or the diagram should have been drawn to show that the 1480 mm length is from the tip to the _bottom_ of the entire assembly. Nicely done document. HTH es 73 Jonesy -- Marvin L Jones | jonz | W3DHJ | linux 38.24N 104.55W | @ config.com | Jonesy | OS/2 *** Killfiling google posts: Article: 227376 of rec.radio.amateur.antenna From: Hans Remeeus Subject: Size of horizontal loop? Date: Sat, 29 Jul 2006 18:53:53 +0200 Message-ID: <4j1i51F5rquhU1@individual.net> Dear all, Next year we will move to another house with a yard of about 1 acre. After 35 years of dipoles finally a horizontal loop is within reach! My most used band is 80 meters for local and mid-European communication. A few times a year I participate in an HF-contest, but I am not a kind of DX'er. I want to feed the horizontal loop with about 200 feet of 600 Ohm open line and use the loop for multiband 160 - 10 meters with a balanced antennatuner. The height of the loop will be about 35 feet and I will use wooden supports for the loop. It am planning to make a full-size loop for 80 meters. However, on this yard it is easy to make a loop of 4 x 100 feet instead of 4 x 70 feet. What is your opinion about the size 400 feet instead of a full-wave for 80 meters? Thanks! -- 73, Hans Remeeus (PA1HR) http://www.remeeus.eu Communication is about people, the rest is technology. Article: 227377 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Size of horizontal loop? Date: 29 Jul 2006 11:00:42 -0700 Message-ID: <1154196042.246932.97630@p79g2000cwp.googlegroups.com> References: <4j1i51F5rquhU1@individual.net> Hans, I don't think it's worth it. The patterns and ground loss of the two antennas at a height of only 35 feet are really very similar. On the other hand, the impedance of the full wave loop according to EZNEC is going to be around 100 ohms resistive, while the 100 foot per side loop has an impedance of about 1500+j3200 ohms. I'd recommend saving the extra 120 feet of wire for other antennas and just building the fullwave. Now, if you want to use the antenna with a tuner at the feedpoint or perhaps open wire feed, the impedance of the 100 foot side loop on 160m is much more reasonable (64-j1300) than the 70 foot per side loop (EZNEC reports 8000-j30000! that is to say, infinite :-) ) 73, Dan Article: 227378 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Radiating Efficiency Date: Sat, 29 Jul 2006 11:03:36 -0700 Message-ID: References: <4jqxg.170368$771.62308@edtnps89> <12clp9b5e3ual1c@corp.supernews.com> On Sat, 29 Jul 2006 08:10:13 +0100, "Reg Edwards" wrote: >Efficiency = Rr / ( Rr + Radials ), which, in the present context, >is incorrect. Hi Reggie, Of course it is incorrect, it is a definition of your own invention. >Efficiency = Rr / ( Rr + Radials + Rsoil ) This is merely an elaboration of the commonplace Efficiency = Rrad / ( Rrad + Rloss ) which you declared >>is very much in error. The error is yours, and your bafflegab that has flowed from this pronouncement of an "error" has been in an effort to cover your tracks. The wonderment you are met with is that you failed to acknowledge that Rloss is commonly accepted to mean more than Ohmic loss. Reggie, the archive is rich with this discussion, and no one but yourself makes the mistake of presuming Rloss has ever meant to be confined to the Ohmic loss of the radiator's metal parts. 73's Richard Clark, KB7QHC Article: 227379 of rec.radio.amateur.antenna Subject: Re: Size of horizontal loop? From: Ed References: <4j1i51F5rquhU1@individual.net> Message-ID: Date: 29 Jul 2006 18:04:53 GMT > > What is your opinion about the size 400 feet instead of a full-wave for > 80 meters? > > > For anybody who can expound on the above question, I'd be interested in the effectiveness of such loops that are a small increase in size over a 80M full-wave size too, such as approximately 300 - 350 feet. I, too, am hoping for useful operation on 160, even though 80M is my primary interest. Ed K7AAT Article: 227380 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Size of horizontal loop? Date: Sat, 29 Jul 2006 11:07:08 -0700 Message-ID: References: <4j1i51F5rquhU1@individual.net> On Sat, 29 Jul 2006 18:53:53 +0200, Hans Remeeus wrote: >What is your opinion about the size 400 feet instead of a full-wave for >80 meters? Hi Hans, An unnecessary change. Also, take care to anticipate that high frequencies into a large antenna create many, many radiation lobes AND nulls that may/may-not be useful. 73's Richard Clark, KB7QHC Article: 227381 of rec.radio.amateur.antenna Subject: Re: Size of horizontal loop? From: Ed References: <4j1i51F5rquhU1@individual.net> <1154196042.246932.97630@p79g2000cwp.googlegroups.com> Message-ID: Date: 29 Jul 2006 18:10:02 GMT > > Now, if you want to use the antenna with a tuner at the feedpoint or > perhaps open wire feed, the impedance of the 100 foot side loop on 160m > is much more reasonable (64-j1300) than the 70 foot per side loop > (EZNEC reports 8000-j30000! that is to say, infinite :-) ) > Dan, I believe the original poster DID indicate he would feed the loop with 600ohm line and a balanced tuner. Could you also run the Z figures for my plan of using a loop of 300 feet of wire on 160? ( 1.9000 MHz ) ... my height will be close to 50 feet, btw. Tnx, Ed K7AAT Article: 227382 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Size of horizontal loop? Date: 29 Jul 2006 11:11:37 -0700 Message-ID: <1154196697.194752.94050@s13g2000cwa.googlegroups.com> References: <4j1i51F5rquhU1@individual.net> K7AAT: A loop of 87.5 feet per side (350 feet total) at 35 feet over average earth shows a feedpoint impedance of 109-j2460 ohms in EZNEC... easier to match than 8800-j30000 for sure. 73, Dan Article: 227383 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Question for You Grounding Gurus Date: Sat, 29 Jul 2006 11:16:47 -0700 Message-ID: References: <1153437176.242544.67620@m79g2000cwm.googlegroups.com> <12cltrq9a4dhpb4@corp.supernews.com> On 29 Jul 2006 08:20:01 -0500, mcalhoun@ksu.edu wrote: >Although I can't cite the reference (I read too many magazines from too >many sources), a recent article somewhere gave a fairly-definitive answer >regarding grounding vs. depth of ground. Hi All, In this last regard, consult: http://www.cpccorp.com/deep.htm However, depth is not the end-all be-all of the subject. Protection can be obtained for far less effort as any AM vertical antenna can give evidence to with its radial system. 73's Richard Clark, KB7QHC Article: 227384 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Size of horizontal loop? Date: 29 Jul 2006 11:16:54 -0700 Message-ID: <1154197014.842366.34830@i3g2000cwc.googlegroups.com> References: <4j1i51F5rquhU1@individual.net> Ed, 517-j7600 for a 300 foot loop at 50 feet still 110-j2500ish for the 350 foot loop at 50 feet. This is a rapid fire thread!! Good point on the multiband original post... didn't read carefully. For 160 meters, the longer the better over an 80m fullwave. Richard has a good point about multiband use but the extra length doesn't change that caveat too much. If you've got an acre of land, it's probably worth thinking about different antennas for the low bands and the higher HF bands. 73, Dan n3ox.dan@gmail.com wrote: > K7AAT: > > A loop of 87.5 feet per side (350 feet total) at 35 feet over average > earth shows a feedpoint impedance of 109-j2460 ohms in EZNEC... easier > to match than 8800-j30000 for sure. > > 73, > Dan Article: 227385 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Help with Antenna Date: Sat, 29 Jul 2006 11:21:07 -0700 Message-ID: <9i9nc2pmkgnn30fteioe7ie16kpobq3caa@4ax.com> References: <_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com> <5sIyg.189329$mF2.162247@bgtnsc04-news.ops.worldnet.att.net> On Sat, 29 Jul 2006 12:24:33 GMT, "Kryptoknight" wrote: >i know i know. the factory one is a dual band 10" antenna (cb and noaa). i'm >looking for the ~27MHz cb band antenna that is approx 12-18" long. this >would have better gain than what i have now, but obviously not like a 1/4 or >1/2 wave antenna. > >any suggestions on through-glass mini "loaded" cb antenna. Hi OM, The difference between an infinitesimal antenna and a quarterwave antenna is only 5%. However, to get the small antenna to resonate brings far more opportunity for loss. 12-18" long is not likely to bring you any advantage but carefree dreams unless you can strangle the loss. 73's Richard Clark, KB7QHC Article: 227386 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: adaptive beamforming Date: Sat, 29 Jul 2006 11:32:25 -0700 Message-ID: <8aanc2p6h0hfglm0ivrr92msl2pbcvr4hm@4ax.com> References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> <44CAD516.9050609@fuse.net> On Fri, 28 Jul 2006 23:25:10 -0400, jawod wrote: >Dave wrote: >> well, 'adaptive beamforming' is two words... >> >> 'beamforming' means forming a directional 'beam' using an antenna. be it a >> simple parasitic array like yagi's or a complex array of driven elements >> like a flat panel radar. ... >> 'adaptive' means forming the beam in a way that makes it work better in the >> environment, or adapt to it's surroundings. ... >Given the need for "stealth" antennas, Is there /are there design(s) >that create small footprint antennas that function as larger traditional > ones? > >Can a longwire be divided into small segments that are independently >controlled such that the sum of the parts behave differently than the >whole?...and can this effect be altered via software? > >Has anyone been working on this approach? Hi John, As David and others offer, this adaptability and beamforming characteristic is a product of both massive duplication and a large area with respect to the wavelength of interest. To put it in rather more traditional terms: "There's no such thing as a free lunch." You ask about controlling small segments independently. Can you imagine that this maze of control wires would in itself be a more capable antenna? This is the price of complexity: if you can afford these elaborations in design, why not do it the traditional way? You gain nothing in sensitivity, you gain nothing in efficiency (which is most certainly the first characteristic to suffer by orders of magnitude). And to offer it as a prospective "stealth" antenna is defeated from the outset. Think of a rather more practical example that is also a good metaphor. Imagine the Fresnel lens. It performs its beamforming through segmentation. Its advantage is that it is lighter than the complete lens, but if you can tolerate the weight, it offers nothing else to compensate for the elaboration of a complex set of lens segments piled one atop the other. Now, if you can pay the price of elaboration, you can spread antenna elements about - disguised even. You can bury control cables and signal cables - you will certainly need them both. You can devise a control program to "focus" the antenna - which is what beamforming is all about. OR you can twist knobs like the thousand armed Shiva to achieve the same thing. For some, this technical challenge alone is worth the struggle - forget the DX. And yes, you will actually gain an advantage over a single fixed antenna. Try with the four square antenna which encompasses all these topics that interest you. If you can wrestle with the knots of its complexity, you can step up to more sophisticated issues. 73's Richard Clark, KB7QHC Article: 227387 of rec.radio.amateur.antenna Subject: Re: Size of horizontal loop? From: Ed References: <4j1i51F5rquhU1@individual.net> <1154196697.194752.94050@s13g2000cwa.googlegroups.com> <1154197014.842366.34830@i3g2000cwc.googlegroups.com> Message-ID: Date: 29 Jul 2006 18:52:32 GMT > Ed, > > 517-j7600 for a 300 foot loop at 50 feet > still 110-j2500ish for the 350 foot loop at 50 feet. > Thank you, Dan. I guess I ought to get myself EZNec sometime! It sounds like what I can put up would "suffice" for 160M occasional operation... I think the MFJ balanced tuner will handle that. Ed Article: 227388 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Size of horizontal loop? Date: 29 Jul 2006 12:15:50 -0700 Message-ID: <1154200550.118153.163090@p79g2000cwp.googlegroups.com> References: <4j1i51F5rquhU1@individual.net> Yeah, Ed, I certainly don't mind doing a few quickie models here and there, happy to do it. It's worth ordering it, though, when you want to do something like I did and model the pattern of your your five element 2m beam 16 inches below your 6m moxon rectangle in the presence of your HF doublet and a nearby aluminum roof, and generate the pattern for eight azimuth directions. It's a great tool to have if you like building antennas, especially if you have complicated, site-specific improvements you might want to do. Dan Article: 227389 of rec.radio.amateur.antenna Date: Sat, 29 Jul 2006 13:38:37 -0600 From: Hank Zoeller Subject: Re: Aluminum tubing for vertical antenna References: <44c07393$0$10058$c3e8da3@news.astraweb.com> <44cb204f_1@news.iprimus.com.au> Message-ID: <44cbba2b$0$10089$c3e8da3@news.astraweb.com> Bitz wrote: > How you gonna tune this beast on all bands? Would be interested to hear > how you going about this. [Not sure you are asking me or Sal about this but I'll answer for me.] Same way the Navy does it! With a Harris RF-601 remote antenna coupler. Only way to go in my view.. But, for the record, I'm not planning on using it on all bands -- only on the bands where it has some chance of being an effective radiator. That's why I'm thinking of either 30' (60 thru 17 meters) or 26' (40 thru 15 meters). 73, -- HZ Article: 227390 of rec.radio.amateur.antenna From: "ferrymanr" References: Subject: Re: Horizontal HF Loop Date: Sat, 29 Jul 2006 20:41:26 +0100 Message-ID: I am currently trying out a horizontal loop on my roof. I live in the trop floor flat and have a 21' x 24' rectangular flat roof with a 3' parapet (low wall) around. The roof is some 30' above ground. I have draped a 21' X 24' loop of wire aroiund this parapet and fed to the tuner with just 6' of 600 ohm ladder line. The tuner is an SGC SG-230 laid on the roof and has its feed cable (combined coax/control/power cable) wound as a choke balun. The tuner is effectively acting as a balanced drive. Results so far. 1. The natural resonance is a little below 40M 2. I can match on all bands from 160M to 10M. 3. It is definitely acting as an NVIS on the LF bands. 4. It works better on LF at night. This could be due to the radiation going upwards and ionosphere reflects LF at night. 5. It acts like an inductive loop pick up for any QRM amanating from the house. 6. Efficiency is generally low. Lobes are all over the place on the HF bands. I will try and raise the loop a foot or two above the parapet tomorrow and see if this helps. Otherwise I am not impressed! I used to get better results with a 30' vertical wire on a fibreglass fishing pole. Unfortunately I don't hasve a good ground for a vertical here and the vertical would cause problems with the local planning authorities. If I can't find a way of making it work better on 80M and 40M I will probably resort to a very short loaded dipole diagonally across the roof. Richard (Dick) G4BBH Article: 227391 of rec.radio.amateur.antenna From: "ferrymanr" References: <10faunulkpj16c9@corp.supernews.com> Subject: Re: Antenna for 80m and limited space Date: Sat, 29 Jul 2006 20:54:53 +0100 Message-ID: As I am also playing with a small horizontal loop (21' x 24') on my roof which is not very efficient I am wondering just what would happen if I made this a two or three turn loop? I can match my present loop OK but efficiency is very low. Richard (Dick) G4BBH "H. Adam Stevens, NQ5H" wrote in message news:10faunulkpj16c9@corp.supernews.com... > Since I've seen no other mention: Three turn loop and a tuner with ladder > line. > Wire length ~100 meters. > Just a thought. > 73 > H. > NQ5H Article: 227393 of rec.radio.amateur.antenna From: "Tam/WB2TT" References: <8829a$44c214d9$4249808e$18884@COMTECK.COM> Subject: Re: AM car radio reception Date: Sat, 29 Jul 2006 16:33:48 -0400 Message-ID: "Jeff Dieterle" wrote in message news:8829a$44c214d9$4249808e$18884@COMTECK.COM... >I posted a few months back about this problem and have narrowed down the >root cause. The symptom are an overpowering hum at the low end of the am >band. It's being caused by a 3-phase distribution line. I can follow this >line in any direction for several miles any time of day with any of my >vehicles and get the interference. I contacted the power company and >supposedly they're going to look for the cause. Has anybody else dealt with >this type of problem? > Maybe somebody knows for sure, but I think BPL starts above the broadcast band. On the other hand, DSL uses lower frequencies, up to about 1000 KHz. I would not expect to have DSL leakage to sound like hum, though. Tam/WB2TT Article: 227394 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: Radiating Efficiency Message-ID: References: <4jqxg.170368$771.62308@edtnps89> <12clp9b5e3ual1c@corp.supernews.com> Date: Sat, 29 Jul 2006 16:37:05 -0400 On Sat, 29 Jul 2006 11:03:36 -0700, Richard Clark wrote: >On Sat, 29 Jul 2006 08:10:13 +0100, "Reg Edwards" > wrote: > >>Efficiency = Rr / ( Rr + Radials ), which, in the present context, >>is incorrect. > >Hi Reggie, > >Of course it is incorrect, it is a definition of your own invention. snip Hi Reg, By any remote chance have you read any of the posts that followed the one you initiated in 'radial attenuation', just below the one we're in now? If not, please do so, and then savor the crow on your plate concerning your somewhat 'stiff' position on BLE's failure to determine the ground characteristics that lie beneath the radials. Thank you. Walt, W2DU Article: 227395 of rec.radio.amateur.antenna From: Hans Remeeus Subject: Re: Size of horizontal loop? Date: Sat, 29 Jul 2006 22:41:11 +0200 Message-ID: <4j1vf7F5tqg6U1@individual.net> References: <4j1i51F5rquhU1@individual.net> <1154196697.194752.94050@s13g2000cwa.googlegroups.com> <1154197014.842366.34830@i3g2000cwc.googlegroups.com> <1154200550.118153.163090@p79g2000cwp.googlegroups.com> Thanks to all for your nteresting information! This evening I found another interesting site about large horizontal loop antennas, including a very simple but effective tool. It can be found on http://www.smeter.net/antennas/rjeloop4.php I will make a horizontal loop of 4 x 25 meters (= 4 x 82 feet) for 160 - 30. And for the higher bands a 14 MHz full-size vertical delta loop. Both with open feeder line. -- 73, Hans Remeeus (PA1HR) http://www.remeeus.eu Communication is about people, the rest is technology. Article: 227396 of rec.radio.amateur.antenna Date: Sat, 29 Jul 2006 14:49:03 -0600 From: Hank Zoeller Subject: Re: Harris RF-2601 auto remote ATU References: <44cae0f7$0$23676$5a62ac22@per-qv1-newsreader-01.iinet.net.au> Message-ID: <44cbc9ee$0$11790$c3e8da3@news.astraweb.com> Bob VK4BYX wrote: > I have the chance to buy a RF-2601 new in its boxes. Can anyone advise me if > an RF-2601 and its control unit are a stand alone installation? The data > sheet advises it is designed to operate with Harris transmitter. Do they > come with an instruction manual? Is further info available? Do you need to > pressurise with nitrogen to achieve full specs of 1KW average power? Here's a quote from the manual: "The fan and case form a heat exchanger which is used to dissipate the heat produced by inductor 1A2L1 (heat producing element). The fan circulates the nitrogen atmosphere over and through the inductor, and then through the air duct between the bottom of the case and the chassis. The heat is transferred to the nitrogen as it passes over the inductor, and then from the nitrogen to the case as it passes through the air duct. The heat is transferred from the case to the outside air and mounting structures by a combination of conduction, convection, and radiation." Keep in mind that the coupler is rated at a kilowatt continuous duty in harsh environments. If your circumstances are kinder and gentler to the equipment you might get away with using pressurized dry air. Me? I use nitrogen. I'm not sure of the controller on the 2601. (I have the RF-601 and the coupler unit itself looks identical to the 2601.) On the RF-601 you can run in automatic mode with an appropriate Harris transmitter (RF-350K, etc.) or you can run in Manual mode where you directly control the tuning. This means you can use the coupler with virtually any source of RF, even ham gear. I think this is what you mean by 'stand alone installation' and, if so, the answer is yes. Harris gear is excellent -- among the best in the world. Buy that thing before someone else gets it.. 73, -- HZ Article: 227397 of rec.radio.amateur.antenna From: ml Subject: heliax vs lmr Message-ID: Date: Sat, 29 Jul 2006 21:45:40 GMT i've read the specs on some healiax and lmr 400 but i can't say that i always can interpert it fully and confused myself basically interperting a real world practical answer if for ex i am going to do some 1296 work and debate what coax is best i compare lmr400 to 1/2i heliax is the heliax much better ? by how much how about lmr 600 vs 1/2in/ and maybe 7/8" heliax is the lmr nearly as good or is the heliax vastly superior? comming here for a tie breaker everyone i asked either gives different answers and non can explain their choice i am not looking for a well lmr is pretty close and cheeper so buy it, price is not the issue i just want to know based on technical spec's if they are only 1db apart it's splitting hairs i'd get the cheepest easist to work w/ after that i just want least loss thanks Article: 227398 of rec.radio.amateur.antenna From: ml Subject: Re: grounding question References: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> <6r2hc2p6rp6vko0p0bbi3gr84ug7gf2dmf@4ax.com> Message-ID: Date: Sat, 29 Jul 2006 21:52:25 GMT In article , Buck wrote: > On Thu, 27 Jul 2006 09:21:41 -0700, Richard Clark > wrote: > > >On Thu, 27 Jul 2006 05:50:23 -0400, Buck wrote: > > > >>It really got me to thinking about what the > >>radio would be like if i had left it plugged in. I unplug my rigs > >>much more often now. > > > >Hi Buck, > > > >Did it get you to thinking about how you replaced the path to ground > >at the time you were unpluggin your rigs? > > > >73's > >Richard Clark, KB7QHC > > It got me to thinking of putting the end of the wire in a jar, which > is what I did. The alternative was to toss it out the window, but > that wasn't viable at the time. i don't think tossing goax into a jar would protect you , dunno but it's good to have a arrestor the good ones have almost not appreciable loss that you would notice on a scanner it will protect it from misc static sudden bursts which u might not unplug fast enough if your luckey it might reduce staticand improve reception couldn't hurt i use some arrestors but when i am not using the ant, i unplug outside the house and ground it it's a choir but i am nutty the other alternative is radio insurrance pretty cheep for just a scnnner naturally it would 'protect' humans best luck Article: 227399 of rec.radio.amateur.antenna From: David Ryeburn Subject: Re: High voltage switch/relays for antenna? Date: Sat, 29 Jul 2006 15:03:57 -0700 Message-ID: References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> In article <1153963913.849931.144990@i42g2000cwa.googlegroups.com>, "TF3KX" wrote: > I am contemplating constructing an antenna where a center-fed HALF WAVE > will be bent in a loop, only to be isolated at the almost-touching ends > by a relay or some other means of a remotely controlled switch. When > the relay contacts are open I will have very high RF voltages between > the contacts, probably "a few KV" or even more. Are there any > suggestions on where I could find a relay, if any, for this? Or any > other means for doing this? I assume that when used on higher frequencies where the antenna is more than 1/2 wave long, the relay contacts are to be closed. If that is what you want to do, and if the higher frequency bands are even multiples of the lower frequency, then you could connect the ends of the 1/2 wave antenna to a shorted 1/4 wave stub made out of open wire. At the lower frequency this would place a very high impedance between the two ends of the antenna, and at even harmonics where the stub would be an integer number of 1/2 waves long, it would place a low impedance between the antenna ends. Cheaper than a relay, too. David, ex-W8EZE -- David Ryeburn ryeburn@sfu.caz To send e-mail, use "ca" instead of "caz". Article: 227400 of rec.radio.amateur.antenna Subject: Re: heliax vs lmr From: Ed References: Message-ID: Date: 29 Jul 2006 22:36:24 GMT The problem you are having comparing heliax to coax is that you are not considering all the parameters. Loss is only one aspect. The biggest difference between most coax and Heliax is physical construction. Heliax, properly installed, with last 10 to even 20 years outdoors before it should be replaced. Coax would deteriorate much much faster. Heliax is a much more "sturdy" product and can also hold up to weather damage better than coax. Being made with a sold jacket also adds to its shielding superiority over most coaxial cables. For most ham use, You'll get the performance you need with coax type cables and not need heliax.... plus your wallet will remain fatter, too. ( I haven't even mentioned the high cost of connectors for Heliax, if you purchase them new.) Ed K7AAT Article: 227401 of rec.radio.amateur.antenna Subject: Re: grounding question From: Ed References: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> <6r2hc2p6rp6vko0p0bbi3gr84ug7gf2dmf@4ax.com> Message-ID: Date: 29 Jul 2006 22:39:07 GMT >> It got me to thinking of putting the end of the wire in a jar, which >> is what I did. The alternative was to toss it out the window, but >> that wasn't viable at the time. Think about that above statement. Do you really think that a lighting strike capable of traveling hundreds or thousands of feet in the air is going to be detered by a couple millimeters of glass, or a couple inches to the opening? Ed K7AAT Article: 227402 of rec.radio.amateur.antenna From: Dan Richardson Subject: Re: Radiating Efficiency Date: Sat, 29 Jul 2006 15:42:33 -0700 Message-ID: References: <4jqxg.170368$771.62308@edtnps89> <12clp9b5e3ual1c@corp.supernews.com> On Sat, 29 Jul 2006 16:37:05 -0400, Walter Maxwell wrote: [snip] > >....... then savor the crow on your plate ...... > >Thank you. > >Walt, W2DU Ah yes Walter, crow on the plate I have had the misfortune of tasting that old bird on many occasions. I found it very tough and not at all palatable. Danny, K6MHE Article: 227403 of rec.radio.amateur.antenna From: Bob Bob Subject: Re: heliax vs lmr References: Message-ID: <0jgtp3-8sj.ln1@p400bob.personal.cox.net> Date: Sat, 29 Jul 2006 21:02:38 -0500 No doubt you'll get a few answers... This is a good URL to compare line loss on; http://www.ocarc.ca/coax.htm A 50 metre run on 1296 of LMR400 is about 7.8dB A 50 metre run of LDF4-50 (1/2" heliax) is about 4.2dB A 50 metre run of LDF5-50 (7/8" heliax) is about 2.3dB You can work out the difference in your install by scaling things proportionally. Dont forget to factor in additonal loss for any mismatch. You then have to ask whether that few dB will make a difference in whatever your mode of operation and interest is. When a RX signal is borderline that dB or two can make a useful difference. Dont forget to factor in the cost of connectors. You may also find both the LMR400 and Andrew cable is too rigid. I'd personally stick to LMR400 simply because I see that as a major step up from (say) RG213 (16dB loss per above) using roughly the same cable diameter. Some of my interest is in low signal 144MHz work but I tend to reduce that problem by using a preamp at the antenna. About the only downside for me using LMR400 is its rigidity and turn radius limitation. I also tend to think in terms of a link budget. Thats easy to do with a path prediction program. (There are some GPL ones out there) Hope this helps Cheers Bob VK2YQA ml wrote: > i've read the specs on some healiax and lmr 400 but i can't say that i > always can interpert it fully and confused myself basically > interperting a real world practical answer Article: 227404 of rec.radio.amateur.antenna Date: Sat, 29 Jul 2006 23:05:56 -0400 From: jawod Subject: Re: adaptive beamforming References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> <44CAD516.9050609@fuse.net> <8aanc2p6h0hfglm0ivrr92msl2pbcvr4hm@4ax.com> Message-ID: <4bdca$44cc2273$453d9423$2851@FUSE.NET> If you can wrestle with the knots of its > complexity, you can step up to more sophisticated issues. > > 73's > Richard Clark, KB7QHC Richard, You need to chill out. I've expressed this before: I don't need your imprimatur to post here. This is an amateur group. As such, speculation on these matters need to be welcomed, not derided. I gladly defer to your expertise. However, I'll not defer to you in speculative matters in an amateur venue. You know, I really hate the term "outside the box", however, naive perspectives, as you seem to deem mine, can be fruitful. Mutual respect is the order of the day. If not, please refrain from responding. "73's" John AB8WH Article: 227405 of rec.radio.amateur.antenna From: "Tom Coates" Subject: 4:1 balun question Date: Sat, 29 Jul 2006 23:40:55 -0400 Message-ID: I'm seeking a 4:1 balun design that could handle >10 watts efficiently on 20M and would be easy to reproduce without purchasing special ferrite cores, etc. There's an old design that puts an electrical half wave of coax between the two connectors on the balanced side. What drawbacks does this old design have compared with more modern ones? Suggestions would be appreciated. Tom, N3IJ Article: 227406 of rec.radio.amateur.antenna Message-ID: <44CC343E.453A8D8C@shaw.ca> From: Irv Finkleman Subject: Re: 4:1 balun question References: Date: Sun, 30 Jul 2006 04:23:21 GMT Tom Coates wrote: > > I'm seeking a 4:1 balun design that could handle >10 watts efficiently on > 20M and would be easy to reproduce without purchasing special ferrite cores, > etc. > > There's an old design that puts an electrical half wave of coax between the > two connectors on the balanced side. > > What drawbacks does this old design have compared with more modern ones? > Suggestions would be appreciated. > > Tom, N3IJ There is an air core balun described in Hints and Kinks 12th Edition 12 trifilar turns (three wires of identical length) of #12 or 14 ecw close wounds on a 1 inch od form. It's a 1:1, but I would think that you could try experimenting and produce a 4:1 without too much trouble. The coax baluns can be heavy and cumbersome -- a simple ferrite bar could be used in lieu of a core. Cores are readily available at most radio wholsalers. For 20 watts you could build a very small but effective balun, This does not fully answer your request but may put you on the right track. You might find some in the newer antenna books. Irv VE6BP -- -------------------------------------- Visit my HomePage at http://members.shaw.ca/finkirv/index.html Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm -------------------- Irv Finkleman, Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP Calgary, Alberta, Canada Article: 227407 of rec.radio.amateur.antenna From: "Sal M. Onella" References: <44c899ce_1@news.iprimus.com.au> Subject: Re: No See Um Antennas underground antenna Message-ID: Date: Sat, 29 Jul 2006 21:40:40 -0700 ... or should it be called "No Hear Um Antennas"? Article: 227408 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: 4:1 balun question References: Message-ID: Date: Sun, 30 Jul 2006 04:47:14 GMT Tom Coates wrote: > There's an old design that puts an electrical half wave of coax between the > two connectors on the balanced side. > What drawbacks does this old design have compared with more modern ones? As with stubs, it is frequency dependent and therefore is limited to a single band. One advantage of a toroid-based transmission line transformer is that it is broad-banded often covering a 10:1 frequency range. If you confine it's use to 20m, the "old design" should work well enough. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227409 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: adaptive beamforming Date: Sat, 29 Jul 2006 21:59:54 -0700 Message-ID: <12cof6c7q0gvj8f@corp.supernews.com> References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> <44CAD516.9050609@fuse.net> It's not a new idea. In a previous life, I worked on the AN/FPS-85 spacetrack radar at Eglin AFB, Florida. This was 1967-68, while it was undergoing acceptance testing. It's a computer-controlled phased array radar with over 5000 separate transmitters and over 4000 separate two-channel (for V and H polarization) receivers, each with its own antenna. At the time, it was controlled by a pair of state-of-the-art IBM 360/30 computers(*). The one I worked on was actually a replacement for an earlier one which was built beginning in 1962 but burned to the ground just as it was completed. (You should have seen the fire control system in the new one!) Radar is, of course, ideally suited for adaptive beam forming, and steering, since both transmitter and receiver are controlled from the same point. The original had some sort of analog variable delay lines, but the replacement had delays switchable by diodes in binary weighted increments. Transmitter and receiver beams could be changed in shape and of course direction, and the receiver beam could be split into several to aid tracking. I believe it's still in use, but undoubtedly with much more capability due to upgrades (see http://www.swri.org/3PUBS/BROCHURE/D10/survrad/survrad.HTM) and the vastly greater computer power now available. If you're interested, there's more about it at http://www.globalsecurity.org/space/systems/an-fps-85.htm and http://www.fas.org/spp/military/program/track/an-fps-85.htm, or you can do a google search of FPS-85. Roy Lewallen, W7EL (*) Apparently the IBMs had a limited amount of non-volatile memory. When the power failed, the programs had to be reloaded. This required about a day of feeding boxes and boxes of Hollerith cards through the reader. Article: 227410 of rec.radio.amateur.antenna From: "Frank's" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Message-ID: Date: Sun, 30 Jul 2006 05:04:45 GMT "Reg Edwards" wrote in message news:ZMedna1TeriXXlfZRVnyuQ@bt.com... > > >> Reg, the radial impedance rapidly converges to 101.6 + j 21.1. >> >> 10 m -- radial Z = 102 + j 20.99 >> 12 m -- radial Z = 101.3 + j 21.1 >> 14 m -- radial Z = 101.65 + j 21.32 >> 16 m -- radial Z = 101.7 + j 21.1 >> 18 m -- radial Z = 101.615 + j 21.1 >> 20 m -- radial Z = 101.61 + j 21.11 >> > ============================================== > Frank, > > Excellent results! The radial has already converged on Zo = 102 + j21 > at a distance of 10 metres. Just where Radial_3 predicts it should. > > The magnitude of Zo is within 20 percent of NEC4 and the impedance > angle is in the right ball-park with the correct sign. > > Now work downwards from 10 metres, to about 7.5 metres, the 3/4-wave > resonant point, to find the point where Zin has truly diverged from > Zo. You will have to work in gradually smaller increments. > > Could you go down to the 1/2-wave resonant point at about 4 metres? > > You will now be able to see what I'm heading for. > > By the way, how much hard labour is all this causing you? Don't try > to tell me what you are actually doing because I havn't the foggiest > idea. > ---- > Reg, This is fairly trivial Reg. It takes me about 90 seconds to run the program, analyze the data, and record the results for each length. I consider this a learning experience. Some of your requests have forced me to read the NEC manual and other books I have on modeling. As a preliminary run I have gone overboard, just to see the overall trend. The fact is I see nothing dramatic happening until the radial gets very short. Possibly you can see regions where I need to concentrate. Obviously most of the steps are very large, and I may have missed something. I would have expected to see a phase reversal though. 9m Zin = 101.8 + j 21.7 8m Zin = 100.5 + j 21.5 7m Zin = 100.5 + j 19.0 6m Zin = 105.1 + j 17.8 5m Zin = 110.5 + j 26.1 4m Zin = 97.0 + j 40.2 3m Zin = 70.5 + j 25.9 2m Zin = 67.2 + j 19.6 I did try steps of 0.1 m from 8 m to 6.7 m, and saw nothing but a progressive trend. Frank Article: 227411 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Help with Antenna Date: Sat, 29 Jul 2006 22:04:44 -0700 Message-ID: <12coffdeliugac1@corp.supernews.com> References: <_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com> <5sIyg.189329$mF2.162247@bgtnsc04-news.ops.worldnet.att.net> <9i9nc2pmkgnn30fteioe7ie16kpobq3caa@4ax.com> Richard Clark wrote: > > The difference between an infinitesimal antenna and a quarterwave > antenna is only 5%. However, to get the small antenna to resonate > brings far more opportunity for loss. 12-18" long is not likely to > bring you any advantage but carefree dreams unless you can strangle > the loss. To clarify, that 5% is only for a lossless antenna. When the antenna becomes very short, you also take a beating in conductor loss, since the currents get enormous, so the antenna itself becomes inefficient. And of course if the antenna depends on current through the ground, you take a beating there for the same reason. So add conductor and possibly ground loss to the inevitable loss in the matching network which must also deal with high current and/or high voltage. Roy Lewallen, W7EL Article: 227412 of rec.radio.amateur.antenna From: "Jerry Martes" References: Subject: Re: 4:1 balun question Message-ID: Date: Sun, 30 Jul 2006 05:27:49 GMT "Tom Coates" wrote in message news:pradnTcKGeASt1HZnZ2dnUVZ_s6dnZ2d@comcast.com... > I'm seeking a 4:1 balun design that could handle >10 watts efficiently on > 20M and would be easy to reproduce without purchasing special ferrite > cores, > etc. > > There's an old design that puts an electrical half wave of coax between > the > two connectors on the balanced side. > > What drawbacks does this old design have compared with more modern ones? > Suggestions would be appreciated. > > Tom, N3IJ Hi Tom If you are interested, I have about 20 new ferrite toroids that arent marked. I wouldnt mind constructing a couple bifilar, 4:1 baluns and connecting them back to bact for loss measurement at 14 MHz. If the prototype works well enough, I could easily measure them at other frequencies from about 5 MHz to 450 MHz. The cores are 1.9 inch OD and 1.4 inch ID and 3/8th thick. I'd expect one toroid to be adequate for power levels around 20 watts. That could probably be estimated after the loss is measured. So, if you are interested, I'll give you a couple cores after I make some measurements on a prototype. I'd do a little research on web published information before building the prototypes. I have build alot of baluns for higher frequencies, but I cant make power on any band. Jerry Again, I am not interested in selling. HAM stuff is my fun time. Article: 227413 of rec.radio.amateur.antenna From: "Sal M. Onella" References: Subject: Re: Capacitive Hat Message-ID: Date: Sat, 29 Jul 2006 22:52:08 -0700 "Reg Edwards" wrote in message news:pYidnbwtGoA0jFfZRVnytg@bt.com... > Sal, > > A capacitance hat allows you to drive your car into the garage without > breaking off a whip of 15 feet equivalent height. > > A capacitance hat loads a short vertical without suffering the loss in > a loading coil. > > To calculate capacitance of a hat, above an antenna of given height, > with N spokes of given length, surrounded by a halo, plus resonant > frequency, download program TOPHAT from website below. > > The program also calculates L and C values of the tuner. The whole > job can be done in a couple of minutes. That's outstanding! I see the original antenna was only about 15% efficient and the capacitance hat improved it by about 2 dB. I will play with that program. Thanks. "Sal" (really KD6VKW) Article: 227414 of rec.radio.amateur.antenna From: im lost Subject: homebrew mobile helical whip antenna using 1.8m CB fiberglass whips info wanted Date: Sun, 30 Jul 2006 17:27:11 +0930 Message-ID: hi got a number of surpuls 1.8m (6ft)fiberglass whip CB antennas looking at making whip antennas for 80,40,30,20 mts got a roll of 1mm copper winding wire and some heatshrink tubing any designs or tips, can you just wind 1/4 wavelenght oner the length of whip or must u have some other winding pitch or base or center loading tight wound coil and good desigens or data on line?? Regards Article: 227415 of rec.radio.amateur.antenna Message-ID: <44CC8BC9.50904@something.com> Date: Sun, 30 Jul 2006 10:36:57 +0000 From: Bitz Subject: Re: homebrew mobile helical whip antenna using 1.8m CB fiberglass References: im lost wrote: > hi got a number of surpuls 1.8m (6ft)fiberglass whip CB antennas > looking at making whip antennas for 80,40,30,20 mts > got a roll of 1mm copper winding wire and some heatshrink tubing > any designs or tips, can you just wind 1/4 wavelenght oner the length > of whip or must u have some other winding pitch or base or center > loading tight wound coil > > and good desigens or data on line?? > > Regards Don't worry theres no "magic" or secret designs when it comes to helical antennas. The Q of such close wound loading is so poor that it barely matters if you place it near the center or the top. This would be the preferred positions rather than at the base. However if you do want to stick with helical winding try and get rid of some of the inductance using a capacity hat. Quite frankly i would ditch the helical winding and use a properly wound center loaded high q coil. You will gain 5 db over any helical design. You can design such a antenna using the Mobile.exe program that comes with the antenna handbook. All my centre or 2/3rds loading coils beat my HyQ Screwdriver so badly that it makes me want to cry. But thats what you have to pay if you want arm chair band changing. Pat Article: 227416 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Date: Sun, 30 Jul 2006 12:33:07 +0100 Message-ID: > This is fairly trivial Reg. It takes me about 90 seconds to run > the program, analyze the data, and record the results for > each length. I consider this a learning experience. Some > of your requests have forced me to read the NEC manual > and other books I have on modeling. > > As a preliminary run I have gone overboard, just to see the > overall trend. The fact is I see nothing dramatic happening > until the radial gets very short. Possibly you can see > regions where I need to concentrate. Obviously most of the steps > are very large, and I may have missed something. I would have > expected to see a phase reversal though. > > 9m Zin = 101.8 + j 21.7 > 8m Zin = 100.5 + j 21.5 > 7m Zin = 100.5 + j 19.0 > 6m Zin = 105.1 + j 17.8 > 5m Zin = 110.5 + j 26.1 > 4m Zin = 97.0 + j 40.2 > 3m Zin = 70.5 + j 25.9 > 2m Zin = 67.2 + j 19.6 > > I did try steps of 0.1 m from 8 m to 6.7 m, and saw nothing > but a progressive trend. > > Frank ========================================= Frank, I'm pleased to hear this does not involve you in a lot of labour. Thanks for the additional useful information. Go back to program Radial_3 for a few minutes and insert our standard inputs. Set the number of radials equal to One. Slowly vary length between 1 and 10 metres while observing Rin + jXin of the radial system. Vary length to find maxima and minima in the value of Rin. Max and min are more pronounced at the shorter lengths due to lower attenuation. Remember, the radial ( transmission line ) is open-circuit at the other end. There is a minimum of Rin when the radial is 1/4-wave resonant at 2.4 metres. There is a maximum of Rin when the radial is 1/2-wave resonant at 4.8 metres. There is another minimum of Rin, but less prominent, when the radial is 3/4-wave resonant at 7.3 metres. As length and attenuation along the line increase, the variations of Rin about its mean become smaller. Eventually, of course, it converges on Ro, the characteristic impedance. ( Ro is also computed but remains constant as length is varied.) There would be a full-wave resonance at approximately 10 metres but it is damped-down into the noise by the attenuation of about 20 dB at that length. Now, what I would like you to do is search for the maxima and and minima in Rin, with their lengths. using NEC4. At some places you may have to use increments of 0.1 metres. If you find any max and minima the values of Rin + jXin will be different from my program and the lengths at which they occur may also differ. I would like to use the information to improve the accuracy of my program on the assumption that NEC4 is more correct when calculating buried radials. ( In this investigation, you may think it peculiar that lengths as small as 0.1 metres should be significant at 8 MHz. This is due to the very low velocity of propagation along buried radials. Program Radial_3 estimates VF.) ---- Reg. Article: 227417 of rec.radio.amateur.antenna From: "hasan schiers" Subject: Re: Radiating Efficiency Date: Sun, 30 Jul 2006 06:39:42 -0500 Message-ID: References: <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> <1154118378.104563.107880@s13g2000cwa.googlegroups.com> You have the right reference, K3LC. I think that's the one used in Devolder's book, Low Band DX'ing. (I don't have it in front of me at the moment) 73, ...hasan, N0AN wrote in message news:1154118378.104563.107880@s13g2000cwa.googlegroups.com... > Reg, this whole thread started because bizarre things happen with > Radial_3 with short radials. > > You can go ahead and put a caveat in it if you like, but it's wrong at > short lengths and that fact needs to be made clear to users of the > program, before they install a radial system of 120 2m radials on 80m > and find that it's a terrible ground system. > > The question that I want answered is how to optimize my radial system, > and I think at this point, I shall be consulting a document entitled > "Maximum Gain Radial Ground Systems for Vertical Antennas" by K3LC. > > Anyone have other suggestions for sources of material for optimum > radial selection given a certain length of wire? > > 73, > Dan > > Reg Edwards wrote: >> Frank, I am not interested is what happens at very short lengths or >> what Radial_3 makes of it. >> >> To determine Zo, start around 10 metres. >> >> If very little happens to input impedance between 10 and and 15 metres >> then you already have Zo = Zin = Ro + jXo. >> >> Neither am I interested in efficiency or antenna input impedance.. >> The problem of Efficiency has already been sorted out. >> > etc. > Article: 227418 of rec.radio.amateur.antenna Date: Sun, 30 Jul 2006 07:55:09 -0400 From: Dave Subject: Re: 4:1 balun question References: <44CC343E.453A8D8C@shaw.ca> Message-ID: Irv Finkleman wrote: REDACTED > > There is an air core balun described in Hints and Kinks 12th Edition > 12 trifilar turns (three wires of identical length) of #12 or 14 ecw > close wounds on a 1 inch od form. It's a 1:1, but I would think that > you could try experimenting and produce a 4:1 without too much trouble. > REDACTED My original balun from 30+ years ago was an airwound balun, commercially manufactured by B&W. It handled 250 watts AM from 80 through 10 meters. If I recall correctly it was two bifilar wound coils, close spaced, about 10 inches long with the series parallel jumpers for 4:1 impedance ratio. /s/ DD W1MCE Article: 227419 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: homebrew mobile helical whip antenna using 1.8m CB fiberglass References: Message-ID: Date: Sun, 30 Jul 2006 12:20:09 GMT im lost wrote: > hi got a number of surpuls 1.8m (6ft)fiberglass whip CB antennas > looking at making whip antennas for 80,40,30,20 mts > got a roll of 1mm copper winding wire and some heatshrink tubing > any designs or tips, can you just wind 1/4 wavelenght oner the length > of whip or must u have some other winding pitch or base or center > loading tight wound coil For good efficiency, use high-Q center loading coils. That means a diameter considerably larger than the diameter of the fiberglass whip. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227420 of rec.radio.amateur.antenna From: "Bob VK4BYX" References: <44cae0f7$0$23676$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <44cbc9ee$0$11790$c3e8da3@news.astraweb.com> Subject: Re: Harris RF-2601 auto remote ATU Date: Sun, 30 Jul 2006 22:48:05 +1000 Message-ID: <44ccaa98$0$1487$5a62ac22@per-qv1-newsreader-01.iinet.net.au> Hank, can you please email me? qrzdotcom Article: 227421 of rec.radio.amateur.antenna From: "Kryptoknight" References: <_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com> <5sIyg.189329$mF2.162247@bgtnsc04-news.ops.worldnet.att.net> <9i9nc2pmkgnn30fteioe7ie16kpobq3caa@4ax.com> <12coffdeliugac1@corp.supernews.com> Subject: Re: Help with Antenna Message-ID: Date: Sun, 30 Jul 2006 13:59:13 GMT so there is no better ducky antenna than the one that came with this cb ?? any suggestions on a roof mounted thin stainless whip?? "Roy Lewallen" wrote in message news:12coffdeliugac1@corp.supernews.com... > Richard Clark wrote: >> >> The difference between an infinitesimal antenna and a quarterwave >> antenna is only 5%. However, to get the small antenna to resonate >> brings far more opportunity for loss. 12-18" long is not likely to >> bring you any advantage but carefree dreams unless you can strangle >> the loss. > > To clarify, that 5% is only for a lossless antenna. When the antenna > becomes very short, you also take a beating in conductor loss, since the > currents get enormous, so the antenna itself becomes inefficient. And of > course if the antenna depends on current through the ground, you take a > beating there for the same reason. So add conductor and possibly ground > loss to the inevitable loss in the matching network which must also deal > with high current and/or high voltage. > > Roy Lewallen, W7EL Article: 227422 of rec.radio.amateur.antenna From: Bob Bob Subject: Re: 4:1 balun question References: Message-ID: <8bpup3-lvk.ln1@p400bob.personal.cox.net> Date: Sun, 30 Jul 2006 08:38:15 -0500 Hi Tom I use a Q section of 100 ohm "coax" (2x 50r cables side by side with shields joined at each end) on my 20m single loop quad (about 140 ohms modeled) I went for the higher load Z (200r) because I wanted a higher SWR b/w and the possibility that it might work on odd multiples (not that there is an amateur band on 42MHz! - Thinking about a 30m version) It seems to work well but it isnt as if I have made any serious comparisons. Its 2:1 SWR b/w is something between about 13.5 and 15MHz. All you need is coax and allowance for velocity factor! Dont know about the balance/unbalance side of things so much. I was getting some shack radiation that a choke balun (turns of coax on an air core) where the feed met the Q didnt seem to help much. The antenna itself is only 8-10m from the shack anyway. I can send you the modeled details if you like. Cheers Bob VK2YQA Tom Coates wrote: > I'm seeking a 4:1 balun design that could handle >10 watts efficiently on > 20M and would be easy to reproduce without purchasing special ferrite cores, > etc. > Article: 227423 of rec.radio.amateur.antenna Message-ID: <44CCCFF5.40000@fuse.net> Date: Sun, 30 Jul 2006 11:27:49 -0400 From: jawod Subject: Re: adaptive beamforming References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> <44CAD516.9050609@fuse.net> <8aanc2p6h0hfglm0ivrr92msl2pbcvr4hm@4ax.com> <4bdca$44cc2273$453d9423$2851@FUSE.NET> jawod wrote: > If you can wrestle with the knots of its > >> complexity, you can step up to more sophisticated issues. >> >> 73's >> Richard Clark, KB7QHC > > > Richard, > > You need to chill out. > > I've expressed this before: I don't need your imprimatur to post here. > This is an amateur group. As such, speculation on these matters need to > be welcomed, not derided. > > I gladly defer to your expertise. However, I'll not defer to you in > speculative matters in an amateur venue. > > You know, I really hate the term "outside the box", however, naive > perspectives, as you seem to deem mine, can be fruitful. Mutual respect > is the order of the day. If not, please refrain from responding. > > "73's" > John > AB8WH Obviously, maybe I'M the one that needs to chill out. Article: 227424 of rec.radio.amateur.antenna From: "Reg Edwards" References: Subject: Re: Capacitive Hat Date: Sun, 30 Jul 2006 17:19:58 +0100 Message-ID: "Sal wrote > That's outstanding! I see the original antenna was only about 15% efficient > and the capacitance hat improved it by about 2 dB. I will play with that > program. Thanks. > ======================================= Sal, enjoy yourself with it. I do not wish to dampen your enthusiam, but 2 dB is only 1/3 of an S-unit. Hardly noticeable! ;o) ;o) ---- Reg. Article: 227425 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: neighborhood antenna restrictions Date: Sun, 30 Jul 2006 09:31:38 -0700 Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> ORIGINAL MESSAGE: On Thu, 27 Jul 2006 15:17:53 GMT, Cecil Moore wrote: >Back in the '50's, Larsen E. Rapp got me with one of those >articles. ------------ REPLY SEPARATOR ------------ One of my favorite Rapp articles was the one about digging a trench, filling it with water and using it as a reflector. QST quit doing April fool articles for a long time, the cowards, but I see they are slowly edging back into it. I miss Larson! Bill, W6WRT Article: 227426 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: base loading vertical with roller inductor? Date: Sun, 30 Jul 2006 09:59:06 -0700 Message-ID: References: <1154100643.691199.3530@b28g2000cwb.googlegroups.com> ORIGINAL MESSAGE: On 28 Jul 2006 08:30:43 -0700, caheaton@netzero.net wrote: >Is there any >reason why this wouldnt' work? Has anybody else modified or built an >antenna using such a system? ------------ REPLY SEPARATOR ------------ I've done it myself and been quite happy. I used a low RPM reversible DC motor to tune it remotely from the shack. Works great. The only suggestion I would make is to not tune it with any significant power to it or you could damage the coil by arcing as the roller moves along. Up to ten or twenty watts should be ok. Keep the roller clean. Bill, W6WRT Article: 227427 of rec.radio.amateur.antenna From: "palaniappan chellappan" Subject: Re: Reflection on Resistive loads Date: 30 Jul 2006 10:27:53 -0700 Message-ID: <1154280473.831241.122890@p79g2000cwp.googlegroups.com> References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> Cecil Moore wrote: > palaniappan chellappan wrote: > > If current and voltage > > are in phase, there is no reflection . am i correct ? > > No. Assuming Z0 is purely resistive, here's what it > takes to make your statement true: > > If current and voltage are in phase *at every point* > up and down a transmission line, there is no reflection. > Thanks for replies, but i couln't able to conclude anything from the two complementary replies i got :-(. Which book is best for learning about concepts like antenna,reflection,swr, etc. I am working only at hf band. If there is any online tutorial ? regards, palam Article: 227428 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Help with Antenna References: <_cSdnaLhdOAX11bZnZ2dnUVZ_vidnZ2d@comcast.com> <5sIyg.189329$mF2.162247@bgtnsc04-news.ops.worldnet.att.net> <9i9nc2pmkgnn30fteioe7ie16kpobq3caa@4ax.com> <12coffdeliugac1@corp.supernews.com> Message-ID: Date: Sun, 30 Jul 2006 18:07:44 GMT Kryptoknight wrote: > so there is no better ducky antenna than the one that came with this cb ?? I made field strength measurements between the abomination that came with my DJ-580 and a Comet CH72S both equipped with a tiger tail. I don't remember the numbers, but the Comet won by a lot. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227429 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Capacitive Hat References: Message-ID: Date: Sun, 30 Jul 2006 18:09:58 GMT Reg Edwards wrote: > Sal, enjoy yourself with it. I do not wish to dampen your enthusiam, > but 2 dB is only 1/3 of an S-unit. Hardly noticeable! ;o) ;o) Hardly noticeable? That's enough to be crowned champion of a 75m mobile shootout with all the attending honors. :-) -- 73, Cecil http://www.qsl.net/w5dxp Article: 227430 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: neighborhood antenna restrictions References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> Message-ID: Date: Sun, 30 Jul 2006 18:13:06 GMT Bill Turner wrote: > QST quit doing April fool articles for a long time, the cowards, but I > see they are slowly edging back into it. QEX is making up for it. From the May/June issue: "I wish to emphasize the fact that the forward and reverse waves really do not exist separately, ..." That's why radar doesn't work. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227431 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Capacitive Hat Date: 30 Jul 2006 11:24:39 -0700 Message-ID: <1154283879.471441.97880@m73g2000cwd.googlegroups.com> References: 1dB is a human-detectable change. 2dB could make the difference between a QSO and no QSO with marginal S/N ratio. 1 "standard" S-unit of 6dB can probably make the difference between marginal S/N and armchair copy. If copy is already armchair, Reg's totally right. No change. I like to make a lot of QSO's that are down in the noise, though. 73, Dan Article: 227432 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Reflection on Resistive loads References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> Message-ID: Date: Sun, 30 Jul 2006 18:29:04 GMT palaniappan chellappan wrote: > Thanks for replies, but i couln't able to conclude anything from the > two complementary replies i got :-(. If the voltage and current are in phase at every point up and down a transmission line (with a resistive Z0), there are no reflections. If there are reflections, the voltage and current are in phase only every 1/4 wavelength. > Which book is best for learning about concepts like > antenna,reflection,swr, etc. I am working only at hf band. If there is > any online tutorial ? Unfortunately, only the older (pre 1990's) ARRL Antenna Books present a decent explanation of reflections. The ARRL has stopped discussing forward and reflected waves and started discussing impedance matching. IMO, it's part of the dumbing down of the ARS along with the rest of the US. Walter Maxwell literally wrote the book on "Reflections". His web page is: http://www.w2du.com Worldradio magazine is on the verge of publishing "Reflections III". Their web page is: http://www.wr6wr.com You might get something useful from my Worldradio magazine article available at: http://www.qsl.net/w5dxp/energy.htm -- 73, Cecil http://www.qsl.net/w5dxp Article: 227433 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: adaptive beamforming Date: 30 Jul 2006 11:33:01 -0700 Message-ID: <1154284381.538609.17940@b28g2000cwb.googlegroups.com> References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> A good design process starts with brainstorming unfettered by practicality. The next step is to take those ideas and start applying filters to the set of ideas you came up with in the first place, and to turn a more pragmatic eye toward the realities of those ideas. In a thread like this, I think that people chime in on different steps of this process. With something like adaptive beamforming, which is not a new idea, a lot of the practicalities have been hashed out and a lot of people already know about them. I think it's worth avoiding the interpretation of responses as reflecting on one's abilities or character or intelligence. Richard is good at pointing out in some detail why a very hard problem is very hard. 73, Dan Article: 227434 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Capacitive Hat References: <1154283879.471441.97880@m73g2000cwd.googlegroups.com> Message-ID: Date: Sun, 30 Jul 2006 18:33:08 GMT n3ox.dan@gmail.com wrote: > I like to > make a lot of QSO's that are down in the noise ... I do believe that meets the definition of masochism. :-) Did you see the T-Shirt? "Life is too short for QRP" -- 73, Cecil http://www.qsl.net/w5dxp Article: 227435 of rec.radio.amateur.antenna From: Buck Subject: Re: grounding question Message-ID: References: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> <6r2hc2p6rp6vko0p0bbi3gr84ug7gf2dmf@4ax.com> Date: Sun, 30 Jul 2006 15:19:58 -0400 >i don't think tossing goax into a jar would protect you , dunno > >but it's good to have a arrestor the good ones have almost not >appreciable loss that you would notice on a scanner > >it will protect it from misc static sudden bursts which u might not >unplug fast enough if your luckey > >it might reduce staticand improve reception > >couldn't hurt i use some arrestors but when i am not using the ant, i >unplug outside the house and ground it it's a choir but i am nutty > >the other alternative is radio insurrance pretty cheep for just a >scnnner naturally it would 'protect' humans > > >best luck After that incident, I read many articles concerning grounding ham equipment, the home, the towers and the antennas. They seem to be different systems, but one thing I learned and most agree on is that the lightning arrester on the coax needs to be one of the chemical versions and not a vanilla gap type arrester. Buck n4pgw -- 73 for now Buck N4PGW Article: 227436 of rec.radio.amateur.antenna From: Buck Subject: Re: grounding question Message-ID: References: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> <6r2hc2p6rp6vko0p0bbi3gr84ug7gf2dmf@4ax.com> Date: Sun, 30 Jul 2006 15:21:26 -0400 On 29 Jul 2006 22:39:07 GMT, Ed wrote: > >>> It got me to thinking of putting the end of the wire in a jar, which >>> is what I did. The alternative was to toss it out the window, but >>> that wasn't viable at the time. > > > > Think about that above statement. Do you really think that a lighting >strike capable of traveling hundreds or thousands of feet in the air is >going to be detered by a couple millimeters of glass, or a couple inches to >the opening? > > > > Ed K7AAT Actually, it wasn't lightning around at that time. the sparks were static burst or something generated from lightning afar off. I was concerned about the possibility of fire when I threw the connector into the jar. Buck -- 73 for now Buck N4PGW Article: 227437 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: Capacitive Hat Date: 30 Jul 2006 12:29:37 -0700 Message-ID: <1154287777.170039.180990@h48g2000cwc.googlegroups.com> References: Hmm... maybe "like" is the wrong word... Whaddya mean, QRP?? I'm running 100W into my 40m dipole on 20m with 100 feet of RG-58! Only 13dB of loss there! That's only 2 and change in S units. I mean, 100W/10^(1.3) = 5.01W... uhoh. Seriously though, a lot of my 6m DX QSO's on CW are within a couple dB of being unreadable, I bet. Probably none on HF right now that could be split this finely, because all my tough ones are being covered by static crashes on 40 and 30m. Back when 15-10m were open, though, I would have welcomed a "1/3 S-unit" increase on some of the hard stuff. Of course, fading is much more than 2dB, but having the average signal level that much higher will still make an *improvement* in readability. 73, Dan Article: 227438 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: grounding question References: <1153993049.021791.283040@i3g2000cwc.googlegroups.com> <6r2hc2p6rp6vko0p0bbi3gr84ug7gf2dmf@4ax.com> Message-ID: Date: Sun, 30 Jul 2006 19:32:30 GMT Buck wrote: > Actually, it wasn't lightning around at that time. the sparks were > static burst or something generated from lightning afar off. I was > concerned about the possibility of fire when I threw the connector > into the jar. That certainly could have been charged particle static buildup. I experienced a similar thing in the Arizona desert when the wind was blowing under clear sky, low humidity conditions. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227439 of rec.radio.amateur.antenna From: "Reg Edwards" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> Subject: Re: Radial attenuation Date: Sun, 30 Jul 2006 20:42:13 +0100 Message-ID: Dear Rich, Try pulling the other leg - it has bells on it! Punchinello Article: 227440 of rec.radio.amateur.antenna From: "an_old_friend" Subject: trolling right along Date: 30 Jul 2006 13:00:25 -0700 Message-ID: <1154289625.473541.127460@b28g2000cwb.googlegroups.com> References: V.E.C. wrote: > NO-CODER LICENSE APPLICATION and EXAM > > (Simplified test approved by all book and magazine publi$her$ and > VE whorehou$e$ who $ay "We need more ham$") troling right along I see Article: 227441 of rec.radio.amateur.antenna From: ml Subject: Re: heliax vs lmr References: <0jgtp3-8sj.ln1@p400bob.personal.cox.net> Message-ID: Date: Sun, 30 Jul 2006 20:00:51 GMT In article <0jgtp3-8sj.ln1@p400bob.personal.cox.net>, Bob Bob wrote: > No doubt you'll get a few answers... > > This is a good URL to compare line loss on; > > http://www.ocarc.ca/coax.htm > > A 50 metre run on 1296 of LMR400 is about 7.8dB > > A 50 metre run of LDF4-50 (1/2" heliax) is about 4.2dB > > A 50 metre run of LDF5-50 (7/8" heliax) is about 2.3dB > > You can work out the difference in your install by scaling things > proportionally. Dont forget to factor in additonal loss for any mismatch. > > You then have to ask whether that few dB will make a difference in > whatever your mode of operation and interest is. When a RX signal is > borderline that dB or two can make a useful difference. > > Dont forget to factor in the cost of connectors. You may also find both > the LMR400 and Andrew cable is too rigid. > > I'd personally stick to LMR400 simply because I see that as a major step > up from (say) RG213 (16dB loss per above) using roughly the same cable > diameter. Some of my interest is in low signal 144MHz work but I tend to > reduce that problem by using a preamp at the antenna. About the only > downside for me using LMR400 is its rigidity and turn radius limitation. > I also tend to think in terms of a link budget. Thats easy to do with a > path prediction program. (There are some GPL ones out there) > > Hope this helps > > Cheers Bob VK2YQA > > ml wrote: > > i've read the specs on some healiax and lmr 400 but i can't say that i > > always can interpert it fully and confused myself basically > > interperting a real world practical answer thanks very much i see the 600 and 1/2 are very close and the 600 is way chubby and hard to work w/plus $$ whereas heliax i think i can find on ebay or hamfair normal sized guess it will last has good shield not too bad to work w/ i think in my applicatioin a 1'x1' shaft few bends on the roof easy and a few in the hallway molding tray prob the hard part :) not counting hoisting it up the shaft the lmr went up ok but it's light adding more coax and antennas are the most fun thanks again al for the help Article: 227442 of rec.radio.amateur.antenna From: "Bob Agnew" References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> Subject: Re: neighborhood antenna restrictions Message-ID: <7C8zg.12390$lv.8869@fed1read12> Date: Sun, 30 Jul 2006 13:26:42 -0700 I also remeber the Scratchfasti Hatchi column in QST in the 50's! "Bill Turner" wrote in message news:pjnpc2lpiknq9obrpanino6ak5jcl9613p@4ax.com... > ORIGINAL MESSAGE: > > On Thu, 27 Jul 2006 15:17:53 GMT, Cecil Moore > wrote: > >>Back in the '50's, Larsen E. Rapp got me with one of those >>articles. > > ------------ REPLY SEPARATOR ------------ > > One of my favorite Rapp articles was the one about digging a trench, > filling it with water and using it as a reflector. > > QST quit doing April fool articles for a long time, the cowards, but I > see they are slowly edging back into it. > > I miss Larson! > > Bill, W6WRT Article: 227443 of rec.radio.amateur.antenna From: "Bob Agnew" References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <1153962517.218150@www.vif.com> <2e0ca$44c9674c$8b370cf3$23161@ALLTEL.NET> Subject: Re: neighborhood antenna restrictions Message-ID: Date: Sun, 30 Jul 2006 13:30:24 -0700 > > If current Laws we enforced, half the population would be behind bars, > and the other half would be guarding them........... > The way my HOA enforces it is to levy a $200 fine in the form of a Mortgage impound on the first violation, with an increasing fine every two weeks thereafter. "Me" wrote in message news:Me-A25784.10574628072006@netnews.worldnet.att.net... > In article , > Cecil Moore wrote: > >> Richard Clark wrote: >> > Consider the source, how many of our "legislator's" have actually >> > stood in arms under that flag? Half their constituency would be >> > behind bars for desecration if the current laws were enforced. >> >> If the current laws were enforced, half the legislators >> would be behind bars. :-) > > If current Laws we enforced, half the population would be behind bars, > and the other half would be guarding them........... > > > Me Article: 227444 of rec.radio.amateur.antenna From: "Reg Edwards" References: Subject: Re: Capacitive Hat Date: Sun, 30 Jul 2006 22:05:11 +0100 Message-ID: Cec, With a generous standard error of 1dB in the measurements, and taking the 3-sigma limits, anybody who has claimed a crown on the strength of 1/3 of an S-unit should be obliged to hand it back to the judges pending the other participants clamour for a re-count. ;o) ---- Reg. Article: 227445 of rec.radio.amateur.antenna From: "TF3KX" Subject: Re: High voltage switch/relays for antenna? Date: 30 Jul 2006 14:16:40 -0700 Message-ID: <1154294200.513141.194630@75g2000cwc.googlegroups.com> References: <1153963913.849931.144990@i42g2000cwa.googlegroups.com> Thanks for the input, everyone. Here are my comments: Power will not be the largest issue here. It will be the high voltage, which will be approx. twice the max. end voltage of a dipole (while one end is at highest pos.V, the other is at highest neg.V). Using a relay will also pose a problem with arcing over to the relay coil and the control cable. In view of this I was hoping someone might have alternative suggestions, such as a home-made, remotely controlled HV-switch. For example, a motor that could use a screwing mechanism to close a contact or to open it - up to a few cm/in gap. There are some suggestions to use a 1/4 wl stub, where opening at one end would pose a zero impedance at the other. But won't I still have the same problem with high voltages - simply moved to the end of the stub instead at the antenna gap? Again - thanks for the input and feel free to contribute further. 73 - TF3KX TF3KX wrote: > Hello: > > I am contemplating constructing an antenna where a center-fed HALF WAVE > will be bent in a loop, only to be isolated at the almost-touching ends > by a relay or some other means of a remotely controlled switch. When > the relay contacts are open I will have very high RF voltages between > the contacts, probably "a few KV" or even more. Are there any > suggestions on where I could find a relay, if any, for this? Or any > other means for doing this? An additional constraint is that the > switching device needs to be light and small (say, 1-2 oz or 20-50 > grams). Some ideas I have come up with are: > > - A small vacuum relay (supplier, type?). > - A home-made relay, providing more contact spacing than usually > available. > - A DC-motor (toy-type) driven mechanism to open and close contacts. > - A mercury switch that could be tilted to make or break the contacts. > - A string-operated switch to open and close the contacts (would run up > the antenna mast). > > Any comments or suggestions? > > 73 - Kristinn, TF3KX Article: 227446 of rec.radio.amateur.antenna From: "Bob Agnew" References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> Subject: Re: QST's Louisiana Loop Message-ID: <73azg.12399$lv.1300@fed1read12> Date: Sun, 30 Jul 2006 15:05:54 -0700 > >>What's a good local source for aluminum tubing? > Here in SoCal it's DIX Metals: http://www.dixmetals.com/ "Richard Clark" wrote in message news:lt5dc21tmmhnc0jd67slhbrndr7m3jdc3n@4ax.com... > On Tue, 25 Jul 2006 18:04:05 -0400, jawod wrote: > >>What's a good local source for aluminum tubing? > > Hi John, > > Look in the yellow pages for "metal shorts." > > 73's > Richard Clark, KB7QHC Article: 227447 of rec.radio.amateur.antenna From: "Bob Agnew" References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> <73azg.12399$lv.1300@fed1read12> Subject: Re: QST's Louisiana Loop Message-ID: Date: Sun, 30 Jul 2006 15:15:09 -0700 Sorry -- I just checked Dix's catalog -- no tubing. Try this one: http://www.saf.com/alumextru.html "Bob Agnew" wrote in message news:73azg.12399$lv.1300@fed1read12... > > >>>What's a good local source for aluminum tubing? >> > Here in SoCal it's DIX Metals: > > http://www.dixmetals.com/ > > > > "Richard Clark" wrote in message > news:lt5dc21tmmhnc0jd67slhbrndr7m3jdc3n@4ax.com... >> On Tue, 25 Jul 2006 18:04:05 -0400, jawod wrote: >> >>>What's a good local source for aluminum tubing? >> >> Hi John, >> >> Look in the yellow pages for "metal shorts." >> >> 73's >> Richard Clark, KB7QHC > > Article: 227448 of rec.radio.amateur.antenna From: "Bob Agnew" References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> Subject: Re: Reflection on Resistive loads Message-ID: Date: Sun, 30 Jul 2006 15:47:03 -0700 > >> Which book is best for learning about concepts like >> antenna,reflection,swr, etc. I am working only at hf band. If there is >> any online tutorial ? > Try these links: http://en.wikipedia.org/wiki/Smith_chart http://en.wikipedia.org/wiki/Reflection_coefficient Don't feel too bad if this subject is not too clear. It used to be introduced in about the fourth semester of Electrical Engineering, usually in Complex Circuit Analysis. Here's the $2 version: Impedance is a complex quantity (i.e. it has both Phase and Magnitude.) The reflection coefficient is a measure of how well a load is matched to its source impedance; the match determines how much power is reflected by the load. Whatever is not reflected, is absorbed by the load. In the case of an antenna, the "load" is free space; therefore all power absorbed by the load is radiated into free space. We would like the reflection coefficient to be 0; when that happens we have a perfect match and all power is radiated. Like impedance, the reflection coefficient has both a phase and a magnitude. When most people talk about the reflection coefficient, they only conside the magnitude and not the phase. "Cecil Moore" wrote in message news:QT6zg.3194$TV.2629@newssvr11.news.prodigy.com... > palaniappan chellappan wrote: >> Thanks for replies, but i couln't able to conclude anything from the >> two complementary replies i got :-(. > > If the voltage and current are in phase at every point up > and down a transmission line (with a resistive Z0), there > are no reflections. If there are reflections, the voltage > and current are in phase only every 1/4 wavelength. > >> Which book is best for learning about concepts like >> antenna,reflection,swr, etc. I am working only at hf band. If there is >> any online tutorial ? > > Unfortunately, only the older (pre 1990's) ARRL Antenna > Books present a decent explanation of reflections. The ARRL > has stopped discussing forward and reflected waves and > started discussing impedance matching. IMO, it's part of > the dumbing down of the ARS along with the rest of the US. > > Walter Maxwell literally wrote the book on "Reflections". His > web page is: http://www.w2du.com Worldradio magazine is on > the verge of publishing "Reflections III". Their web page > is: http://www.wr6wr.com > > You might get something useful from my Worldradio magazine > article available at: http://www.qsl.net/w5dxp/energy.htm > -- > 73, Cecil http://www.qsl.net/w5dxp Article: 227449 of rec.radio.amateur.antenna From: "Bob Agnew" References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> Subject: Re: Reflection on Resistive loads Message-ID: Date: Sun, 30 Jul 2006 16:04:10 -0700 Just a nit: You said: > If there are reflections, the voltage > and current are in phase only every 1/4 wavelength. Actually, if there are reflections, the voltage and current ar NEVER in phase. "Cecil Moore" wrote in message news:QT6zg.3194$TV.2629@newssvr11.news.prodigy.com... > palaniappan chellappan wrote: >> Thanks for replies, but i couln't able to conclude anything from the >> two complementary replies i got :-(. > > If the voltage and current are in phase at every point up > and down a transmission line (with a resistive Z0), there > are no reflections. If there are reflections, the voltage > and current are in phase only every 1/4 wavelength. > >> Which book is best for learning about concepts like >> antenna,reflection,swr, etc. I am working only at hf band. If there is >> any online tutorial ? > > Unfortunately, only the older (pre 1990's) ARRL Antenna > Books present a decent explanation of reflections. The ARRL > has stopped discussing forward and reflected waves and > started discussing impedance matching. IMO, it's part of > the dumbing down of the ARS along with the rest of the US. > > Walter Maxwell literally wrote the book on "Reflections". His > web page is: http://www.w2du.com Worldradio magazine is on > the verge of publishing "Reflections III". Their web page > is: http://www.wr6wr.com > > You might get something useful from my Worldradio magazine > article available at: http://www.qsl.net/w5dxp/energy.htm > -- > 73, Cecil http://www.qsl.net/w5dxp Article: 227450 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: Reflection on Resistive loads Message-ID: References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> Date: Sun, 30 Jul 2006 19:24:16 -0400 On Sun, 30 Jul 2006 16:04:10 -0700, "Bob Agnew" wrote: >Just a nit: You said: > >> If there are reflections, the voltage >> and current are in phase only every 1/4 wavelength. > >Actually, if there are reflections, the voltage and current ar NEVER in >phase. In fact, voltage and current in the reflected wave are ALWAYS 180° out of phase, while in the forward wave they are always in phase. Thus, along the line they alternately add and subtract, first reinforcing and then cancelling each other at every quarter wave, to form the standing wave. Walt, W2DU > Article: 227451 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Capacitive Hat References: Message-ID: Date: Sun, 30 Jul 2006 23:50:16 GMT Reg Edwards wrote: > With a generous standard error of 1dB in the measurements, and taking > the 3-sigma limits, anybody who has claimed a crown on the strength of > 1/3 of an S-unit should be obliged to hand it back to the judges > pending the other participants clamour for a re-count. ;o) I have a confession to make, Reg. I noticed precipitation water from the fog dripping from everyone's coils when the measurements first started. I waited until last when the sun was shining and won the shootout. :-) -- 73, Cecil http://www.qsl.net/w5dxp Article: 227452 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Reflection on Resistive loads References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> Message-ID: Date: Sun, 30 Jul 2006 23:54:03 GMT Bob Agnew wrote: > Just a nit: You said: > >> If there are reflections, the voltage >> and current are in phase only every 1/4 wavelength. > > Actually, if there are reflections, the voltage and current ar NEVER in > phase. So how does a 1/2WL piece of transmission line driving a 50 ohm load wind up with the voltage and current in phase no matter what the SWR? -- 73, Cecil http://www.qsl.net/w5dxp Article: 227453 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Reflection on Resistive loads References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> Message-ID: <4Ibzg.77884$Lm5.22750@newssvr12.news.prodigy.com> Date: Sun, 30 Jul 2006 23:57:52 GMT Walter Maxwell wrote: > On Sun, 30 Jul 2006 16:04:10 -0700, "Bob Agnew" wrote: >> Actually, if there are reflections, the voltage and current ar NEVER in >> phase. > > In fact, voltage and current in the reflected wave are ALWAYS 180° out of phase, > while in the forward wave they are always in phase. Thus, along the line they > alternately add and subtract, first reinforcing and then cancelling each other > at every quarter wave, to form the standing wave. All true, Walt, but I think we are discussing the net voltage and net current which are in phase only every 1/4 wavelength where the SWR circle crosses the horizontal purely resistive line on the Smith Chart. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227454 of rec.radio.amateur.antenna Date: Sun, 30 Jul 2006 20:29:11 -0400 From: jawod Subject: Re: QST's Louisiana Loop References: <84cc2$44c28fbc$453d9423$18240@FUSE.NET> <73azg.12399$lv.1300@fed1read12> Message-ID: Bob Agnew wrote: > Sorry -- I just checked Dix's catalog -- no tubing. Try this one: > > http://www.saf.com/alumextru.html > > > "Bob Agnew" wrote in message > news:73azg.12399$lv.1300@fed1read12... > >>>>What's a good local source for aluminum tubing? >>> >>Here in SoCal it's DIX Metals: >> >>http://www.dixmetals.com/ >> >> >> >>"Richard Clark" wrote in message >>news:lt5dc21tmmhnc0jd67slhbrndr7m3jdc3n@4ax.com... >> >>>On Tue, 25 Jul 2006 18:04:05 -0400, jawod wrote: >>> >>> >>>>What's a good local source for aluminum tubing? >>> >>>Hi John, >>> >>>Look in the yellow pages for "metal shorts." >>> >>>73's >>>Richard Clark, KB7QHC >> >> > > Thanks, Bob. You know, I couldn't find any at Lowes but, surprisingly, I did find SOME at a neighborhood hardware store. Article: 227455 of rec.radio.amateur.antenna From: "Brian Denley" References: Subject: Re: New No-code HF Pro-Technology Exam Date: Sun, 30 Jul 2006 21:09:44 -0400 Message-ID: That's ridiculous! Many exisiting hams couldn't pass it! -- Brian Denley http://home.comcast.net/~b.denley/index.html "V.E.C." wrote in message news:arrl.vec.sej0rf-sdofcvkw-sodkmv@arrl.vec... > > NO-CODER LICENSE APPLICATION and EXAM > > (Simplified test approved by all book and magazine publi$her$ and > VE whorehou$e$ who $ay "We need more ham$") > > Please PRINT (that means no squiggly lines) > Article: 227456 of rec.radio.amateur.antenna Message-ID: <44CD62D5.1050200@biggun.com> Date: Mon, 31 Jul 2006 01:54:29 +0000 From: P Finklestein Subject: Re: adaptive beamforming References: <383cb$44ca7ea7$d844b81d$19205@FUSE.NET> <9tadnb9wN7gIHFfZnZ2dnUVZ_q2dnZ2d@crocker.com> <44CAD516.9050609@fuse.net> <8aanc2p6h0hfglm0ivrr92msl2pbcvr4hm@4ax.com> <4bdca$44cc2273$453d9423$2851@FUSE.NET> <44CCCFF5.40000@fuse.net> <1154284381.538609.17940@b28g2000cwb.googlegroups.com> n3ox.dan@gmail.com wrote: > A good design process starts with brainstorming unfettered by > practicality. The next step is to take those ideas and start applying > filters to the set of ideas you came up with in the first place, and to > turn a more pragmatic eye toward the realities of those ideas. > > In a thread like this, I think that people chime in on different steps > of this process. With something like adaptive beamforming, which is > not a new idea, a lot of the practicalities have been hashed out and a > lot of people already know about them. > > I think it's worth avoiding the interpretation of responses as > reflecting on one's abilities or character or intelligence. Richard is > good at pointing out in some detail why a very hard problem is very > hard. > > 73, > Dan > Besides if it was so simple, MFJ would have had a product for sale by now! Pat Article: 227457 of rec.radio.amateur.antenna From: "Steve Stone" References: Subject: CW to be used in Beruit as only means of communication by Coast Guard Message-ID: Date: Mon, 31 Jul 2006 02:21:12 GMT The Coast Guard reported today that they will only use CW in Beruit. All other emissions will be ignored. Article: 227458 of rec.radio.amateur.antenna From: "an_old_friend" Subject: realy? Date: 30 Jul 2006 19:26:58 -0700 Message-ID: <1154312818.147850.15080@i42g2000cwa.googlegroups.com> References: Steve Stone wrote: > The Coast Guard reported today that they will only use CW in Beruit. > All other emissions will be ignored. right Article: 227459 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: Capacitive Hat Date: Sun, 30 Jul 2006 20:16:04 -0700 Message-ID: <7etqc2pt6tifefokpquk3cgrhsc07dsbff@4ax.com> References: ORIGINAL MESSAGE: On Sun, 30 Jul 2006 18:09:58 GMT, Cecil Moore wrote: >Hardly noticeable? That's enough to be crowned champion >of a 75m mobile shootout with all the attending honors. :-) >-- ------------ REPLY SEPARATOR ------------ Speaking of shootouts, are there any scheduled this summer? I've never been to one and I'd love to go. Bill, W6WRT Article: 227460 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: neighborhood antenna restrictions Date: Sun, 30 Jul 2006 20:20:35 -0700 Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> <7C8zg.12390$lv.8869@fed1read12> ORIGINAL MESSAGE: On Sun, 30 Jul 2006 13:26:42 -0700, "Bob Agnew" wrote: >I also remeber the Scratchfasti Hatchi column in QST in the 50's! ------------ REPLY SEPARATOR ------------ I remember too, but I don't think it was QST. Either CQ or 73 I'm pretty sure. Bill, W6WRT Article: 227461 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: New No-code HF Pro-Technology Exam Date: Sun, 30 Jul 2006 20:27:52 -0700 Message-ID: <8ttqc2pn2n7upib6tkcssjcrsf5d93epb4@4ax.com> References: ORIGINAL MESSAGE: On Sun, 30 Jul 2006 19:40:22 GMT, ve@arrl.biz (V.E.C.) wrote: >3. “HEADPHONES” are worn over the ___________. > > A. Knees > B. Eyes > C. Toes > D. Ears > E. Lips ------------ REPLY SEPARATOR ------------ Damn! Failed number 3. My headphones are always in a drawer but that wasn't one of the choices. My toephones, on the other hand are right where they are supposed to be. Bill, W6WRT whose spell checker choked on that one for some reason Article: 227462 of rec.radio.amateur.antenna Date: Sun, 30 Jul 2006 23:28:14 -0400 From: jawod Subject: Re: CW to be used in Beruit as only means of communication by Coast References: Message-ID: <91a46$44cd7933$453d9423$27613@FUSE.NET> Steve Stone wrote: > The Coast Guard reported today that they will only use CW in Beruit. > All other emissions will be ignored. > > Steve, Can you provide a source for this report? Article: 227463 of rec.radio.amateur.antenna From: Bob Nielsen Subject: Re: neighborhood antenna restrictions Date: Sun, 30 Jul 2006 20:45:54 -0700 Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> <7C8zg.12390$lv.8869@fed1read12> On Sun, 30 Jul 2006 21:20:35 -0700, Bill Turner wrote: > ORIGINAL MESSAGE: > > On Sun, 30 Jul 2006 13:26:42 -0700, "Bob Agnew" > wrote: > >>I also remeber the Scratchfasti Hatchi column in QST in the 50's! > > ------------ REPLY SEPARATOR ------------ > > I remember too, but I don't think it was QST. Either CQ or 73 I'm > pretty sure. > > Bill, W6WRT It was Hashifisti Scratchi and was in in CQ (before 73 existed). I heard that it originated in "Radio", but that was before my time.... Bob, N7XY Article: 227464 of rec.radio.amateur.antenna Message-ID: From: jimp@specsol.spam.sux.com Subject: Re: CW to be used in Beruit as only means of communication by Coast Guard References: Date: Mon, 31 Jul 2006 03:55:02 GMT In rec.radio.amateur.antenna Steve Stone wrote: > The Coast Guard reported today that they will only use CW in Beruit. > All other emissions will be ignored. Who's Coast Guard would that be? -- Jim Pennino Remove .spam.sux to reply. Article: 227465 of rec.radio.amateur.antenna Subject: Re: CW to be used in Beruit as only means of communication by Coast Guard From: Ed References: Message-ID: Date: 31 Jul 2006 04:21:23 GMT jimp@specsol.spam.sux.com wrote in news:u4b0q3-fgk.ln1@mail.specsol.com: > In rec.radio.amateur.antenna Steve Stone wrote: >> The Coast Guard reported today that they will only use CW in Beruit. >> All other emissions will be ignored. > Who's Coast Guard would that be? > US Coast Guard is involved in the evacuation of US citizens in Lebanon at the Port in Beirut. However, I'd like to see the source of the above claim about CW. Ed K7AAT Article: 227466 of rec.radio.amateur.antenna From: "Sal M. Onella" References: Subject: Re: Capacitive Hat Message-ID: Date: Sun, 30 Jul 2006 21:37:47 -0700 "Reg Edwards" wrote in message news:wd-dnX-acv72QVHZRVnyjA@bt.com... > > "Sal wrote > > That's outstanding! I see the original antenna was only about 15% > efficient > > and the capacitance hat improved it by about 2 dB. I will play with > that > > program. Thanks. > > > ======================================= > Sal, enjoy yourself with it. I do not wish to dampen your enthusiam, > but 2 dB is only 1/3 of an S-unit. Hardly noticeable! ;o) ;o) Agreed. What appealed to me was that the difference was so easily calculated with your program. I simply reran the program with the hat reduced to miniscule size and observed the difference. This was an AM broadcast station (Armed Forces Radio Service), so the difference was not likely to have been audible. The tech who put the hat on the whip may just have been making it easier to match. It was forty years ago. Article: 227467 of rec.radio.amateur.antenna From: "an_old_friend" Subject: Re: CW to be used in Beruit as only means of communication by Coast Guard Date: 30 Jul 2006 22:03:35 -0700 Message-ID: <1154322215.855013.62940@i3g2000cwc.googlegroups.com> References: Ed wrote: > jimp@specsol.spam.sux.com wrote in news:u4b0q3-fgk.ln1@mail.specsol.com: > > > In rec.radio.amateur.antenna Steve Stone wrote: > >> The Coast Guard reported today that they will only use CW in Beruit. > >> All other emissions will be ignored. > > > > Who's Coast Guard would that be? > > > > > US Coast Guard is involved in the evacuation of US citizens in Lebanon > at the Port in Beirut. However, I'd like to see the source of the above > claim about CW. given the poster is all but an annnymouse the source is likely out thier ass > > > Ed K7AAT Article: 227468 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: 4:1 balun question Message-ID: References: Date: Mon, 31 Jul 2006 05:24:16 GMT On Sat, 29 Jul 2006 23:40:55 -0400, "Tom Coates" wrote: >I'm seeking a 4:1 balun design that could handle >10 watts efficiently on >20M and would be easy to reproduce without purchasing special ferrite cores, >etc. > >There's an old design that puts an electrical half wave of coax between the >two connectors on the balanced side. > >What drawbacks does this old design have compared with more modern ones? >Suggestions would be appreciated. You asked for a balun for one band. Your proposed solution works fine. It is a narrowband solution, which is fine if you only want to work 20m. Very widely used on VHF Yagis which are narrowband applications. Some have written that the loss in feed to one side of the balanced load (~0.2dB for RG213 at 20m) causes significant pattern distortion. However, most baluns are not perfectly balanced. Owen -- Article: 227469 of rec.radio.amateur.antenna From: "Reg Edwards" References: Subject: Re: Capacitive Hat Date: Mon, 31 Jul 2006 06:26:37 +0100 Message-ID: <59Cdnei4YadZCVDZRVnyiQ@bt.com> "Cecil Moore" wrote > I have a confession to make, Reg. I noticed precipitation > water from the fog dripping from everyone's coils when > the measurements first started. I waited until last when > the sun was shining and won the shootout. :-) > -- ======================================== Cec, now that's really making science work for you. I can imagine you in a deer-stalker capacitance hat, using a Sherlock Holmes magnifying glass to read the S-meter. ---- Reg. Article: 227470 of rec.radio.amateur.antenna From: The Kat Subject: Re: CW to be used in Beruit as only means of communication by Coast Guard Message-ID: <3ibrc2lls24738cpkqi5cp5g6gdmkofjag@4ax.com> References: Date: Mon, 31 Jul 2006 07:16:11 GMT On Mon, 31 Jul 2006 02:21:12 GMT, "Steve Stone" wrote: >The Coast Guard reported today that they will only use CW in Beruit. >All other emissions will be ignored. Of COURSE they did. Lumber Cartel (tinlc) #2063. Spam this account at your own risk. This sig censored by the Office of Home and Land Insecurity... Remove XYZ to email me Article: 227471 of rec.radio.amateur.antenna From: "A.E. 352" References: Subject: Re: New No-code HF Pro-Technology Exam Message-ID: Date: Mon, 31 Jul 2006 07:46:22 GMT YAWN... and to think that the 'Liberty Net' folks had to pass a harder test than this dribble. "V.E.C." wrote in message news:arrl.vec.sej0rf-sdofcvkw-sodkmv@arrl.vec... > > NO-CODER LICENSE APPLICATION and EXAM > > (Simplified test approved by all book and magazine publi$her$ and > VE whorehou$e$ who $ay "We need more ham$") > > Please PRINT (that means no squiggly lines) > > YOUR NAME (what they call you) > __________________________________________ > > ADDRESS (where you live) _______________________________________________ > > BIRTHDATE (when you were born) ________________________________ > > EXAM > > Instructions: Make a circle (one of these round things O ) around the > letter of the best answer! This is so we know what your answer to the > question is! > > 1. You TALK into a microphone with your _______. > > A. Hands > B. Feet > C. Toes > D. Mouth > E. Armpits > > 2. When you talk into a microphone, you talk into _______. > > A. the front > B. the back > C. the top > D. the bottom > E. the wire > > 3. "HEADPHONES" are worn over the ___________. > > A. Knees > B. Eyes > C. Toes > D. Ears > E. Lips > > 4. What do you do with the AC line cord coming out of a power supply? > > A. Hold it in the air to pick up signals > B. Pull on it to start the motor > C. Talk into the plug to get real "skip DX" > D. Hook it to your antenna > E. Insert the plug into a source of power > > 5. A "two meter" radio is: > > A. twice as strong as a one-meter radio > B. two one-meter radios in series > C. a CB with two meters on the front panel > D. a good doorstop > E. yo mama > > 6. A "ten-foot mast" is how long? > > A. Ten feet > B. Ten pounds > C. Two meters > D. Tree-top tall > E. yo mama > > 7. A "Triband antenna" is made to work on how many bands? > > A. 1 > B. 2 > C. 3 > D. 4 > E. 10 > > 8. The "Marconi" antenna is named after: > > A. Marconi > B. Mantovani > C. macaroni > D. Dean Martin > E. yo mama > > 9. What colors of DIODES can you buy at a Radio Shack store? > > A. Red, blue and black > B. Red, yellow and green > C. Orange and brown > D. I am colorblind so this is a discriminatory question and I should > automatically get my license because you have been mean to me. > E. I have no intention of ever using DIODES, so I should get my > license for free. > > 10. What color of SLURPEE can you buy at 7-11? > > A. Red, blue and black > B. Red, yellow and green > C. Orange and brown > D. I am colorblind so this is a discriminatory question and I should > automatically get my license and free slurpees forever because you > have been mean to me. > > END OF EXAM. > > YOUR SIGNATURE (slap yo tag here) > _________________________________________ > > Scoring: > > Get THREE correct and you get an EXTRA!!!! > Get TWO right and you get an ADVANCED!!!! > Get ONE right and you get a GENERAL!!! > Blow them all? Just blow the VE and get any license you want!!! Article: 227472 of rec.radio.amateur.antenna From: "Harbin Osteen" References: Subject: Re: Coax recomendations Date: Mon, 31 Jul 2006 03:17:04 -0700 Message-ID: Howdy: I was wondering if, for a long run, instead of running coax for vhf or uhf, if you could have your radio up by the antenna, then run some large, but cheep wire to the head unit on say a ic-208? Would there be too much loss in D.C., or is there any other problems that I don't know about that would make this a really stupid idea, such as some kind of timing delay problem? -- SeeYaa:) Harbin Osteen KG6URO !sdohtem noitpyrcne devorppa-tnemnrevog troppus I - Article: 227473 of rec.radio.amateur.antenna From: "Neil Long" Subject: Hi there Date: 31 Jul 2006 04:05:45 -0700 Message-ID: <1154343945.104639.234110@i42g2000cwa.googlegroups.com> Hi from Neil Long and Radio Jackie in SW London Hi there, my name is Neil Long, I am a radio presenter on a station in SW London called Radio Jackie, formally pirate, now legal! www.radiojackie.com. I have a blog site that I would be delighted for you to visit on http://getintoradio.blogspot.com All the very best Neil Article: 227474 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Reflection on Resistive loads Date: Mon, 31 Jul 2006 04:54:01 -0700 Message-ID: <12crrqrljfra196@corp.supernews.com> References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> Walter Maxwell wrote: > On Sun, 30 Jul 2006 16:04:10 -0700, "Bob Agnew" wrote: > >> Just a nit: You said: >> >>> If there are reflections, the voltage >>> and current are in phase only every 1/4 wavelength. >> Actually, if there are reflections, the voltage and current ar NEVER in >> phase. > > In fact, voltage and current in the reflected wave are ALWAYS 180° out of phase, > while in the forward wave they are always in phase. Thus, along the line they > alternately add and subtract, first reinforcing and then cancelling each other > at every quarter wave, to form the standing wave. > > Walt, W2DU And, if you assume the line is lossless, the voltage and current are in phase every 90 degrees along the line regardless of the amount of mismatch. This is easily illustrated with a Smith chart -- choose any point you'd like, representing an arbitrary load impedance. Then draw a circle through that point, with the center of the circle at the chart's origin. Moving clockwise along this circle represents moving along the transmission line from the load toward the source. You'll cross the chart's axis, where the impedance is purely real, in a half revolution (90 degrees of movement along the line) or less, and cross it each half revolution (90 degrees) from then on. Roy Lewallen, W7EL Article: 227475 of rec.radio.amateur.antenna From: David George Johnson Subject: effect of metal pipe supporting a vertical cage antenna Date: Mon, 31 Jul 2006 08:12:41 -0400 Message-ID: I want to put an eight wire vertical cage around a one hundred twenty foot steel support for 80 meters. I can center feed the cage with open wire line, which I assume will be more efficient than feeding the steel at the bottom. The cage will not be in contact with the ground or the tower. My thought is that the wires will make a better radiator than the steel, but I have no idea what the steel "core" will do to the efficiency of the antenna. I have had no success in modelling this antenna. So my question is will the center fed, ungrounded cage dipole provide any real advantage over feeding the tower at the bottom? Thanks. Dave Article: 227476 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Capacitive Hat References: <7etqc2pt6tifefokpquk3cgrhsc07dsbff@4ax.com> Message-ID: Date: Mon, 31 Jul 2006 13:11:50 GMT Bill Turner wrote: > Speaking of shootouts, are there any scheduled this summer? I've never > been to one and I'd love to go. I haven't heard of any. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227477 of rec.radio.amateur.antenna From: "n3ox.dan@gmail.com" Subject: Re: effect of metal pipe supporting a vertical cage antenna Date: 31 Jul 2006 06:13:58 -0700 Message-ID: <1154351638.030992.325150@75g2000cwc.googlegroups.com> References: There is going to be a LOT of coupling from the two halves of the cage dipole to the tower. It sounds like a recipe for disappointment to me. As far as a radiator, the steel will work OK because it's got a lot of surface area. You could always cage it with wires connected at the top and bottom if you're worried about the conductivity. I'd feed it at the bottom if I was lucky enough to have a 120 foot vertical pipe :-) 73, Dan Article: 227478 of rec.radio.amateur.antenna Date: Mon, 31 Jul 2006 06:15:16 -0700 From: "R. Scott" Subject: Re: New No-code HF Pro-Technology Exam References: Message-ID: V.E.C. wrote: > NO-CODER LICENSE APPLICATION and EXAM I bet you fought AM and SSB too. Article: 227479 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Coax recomendations References: Message-ID: Date: Mon, 31 Jul 2006 13:18:35 GMT Harbin Osteen wrote: > Howdy: > I was wondering if, for a long run, instead of running coax for vhf or > uhf, if you could > have your radio up by the antenna, then run some large, but cheep wire to > the head unit > on say a ic-208? Would there be too much loss in D.C., or is there any other > problems > that I don't know about that would make this a really stupid idea, such as > some kind > of timing delay problem? Locating an amplifier at the antenna is a fairly common practice both for transmitting and/or receiving. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227480 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Reflection on Resistive loads References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> <12crrqrljfra196@corp.supernews.com> Message-ID: Date: Mon, 31 Jul 2006 13:59:38 GMT Roy Lewallen wrote: > And, if you assume the line is lossless, the voltage and current are in > phase every 90 degrees along the line regardless of the amount of mismatch. If the line has losses, the SWR circle becomes an SWR spiral but the spiral still crosses the purely resistive axis like the circle does, just not at the same points. Does your answer imply that the number of degrees between purely resistive crossings is not equal to 90 degrees when the line is lossy? (Not a trick question) -- 73, Cecil http://www.qsl.net/w5dxp Article: 227481 of rec.radio.amateur.antenna From: Bob Bob Subject: Re: Coax recomendations References: Message-ID: Date: Mon, 31 Jul 2006 09:04:41 -0500 Remoting radios is nothing new and quite do-able. Signal line loss problems depend on the design of the remoting. ie if line drivers are used, not a problem. If high Z TTL lines then you might have a problem. Power supply will be a problem. It may be smart to also remote a large battery for current peaks. Easy to work out... You may wish to address other issues though like lightning strikes and weather ingress.. I use to remote a linear amp and preamp with a remote NiCd pack of D cells. Worked well. RFO was about 70W on 144MHz. Open wire feeder may also be an option to you.. The line loss would be lower. You could also make some out of small dia copper pipe and spacers you size/drill yourself. Cheers Bob VK2YQA Harbin Osteen wrote: > Howdy: > I was wondering if, for a long run, instead of running coax for vhf or > uhf, if you could Article: 227482 of rec.radio.amateur.antenna From: "Denny" Subject: Re: effect of metal pipe supporting a vertical cage antenna Date: 31 Jul 2006 08:10:04 -0700 Message-ID: <1154358604.340852.309140@s13g2000cwa.googlegroups.com> References: You will find hanging a dipole next to a conductor will couple heavily... I suspect your cage dipole around the tower will cause you grief... There has been lots of discussion on feeding galvanized steel towers with RF... The consensus is that the surface area of the tower makes up for it's lower conductivity... There appears to be little/nothing to be gained by straping a few, small diameter wires to the surface of the tower... I have run 160 meter receiving tests where I switched between a steel quarter wave tower and a sloping vertical wire hung off another tower 240 feet away... Both monopole antennas a resonant quarter wave on 160... Relays used to detune the unused monopole.. There is no difference in the received signal strengths that I can find... At least for 80 and 160 I have no qualms about feeding the tower... I used to be a believer in adding wires up the tower face, but I have found the rapture... If your tower is grounded and it is more than a quarter wave in height, you can make it into a folded unipole to allow feeding at the bottom... This will raise the feedpoint impedence, so you will have to use a parallel resonant tank circuit to match it... I find this better (in my twisted mind) than taping a few feet up the tower for a feed point... ymmv... cheers ... denny - k8do Article: 227483 of rec.radio.amateur.antenna From: Bill Turner Subject: Re: New No-code HF Pro-Technology Exam Date: Mon, 31 Jul 2006 08:35:34 -0700 Message-ID: References: ORIGINAL MESSAGE: On Mon, 31 Jul 2006 07:46:22 GMT, "A.E. 352" wrote: >YAWN... and to think that the 'Liberty Net' folks had to pass a harder test >than this dribble. ------------ REPLY SEPARATOR ------------ Be nice. I thought it was a great spoof. Bill, W6WRT 20 wpm extra Article: 227484 of rec.radio.amateur.antenna From: "Denny" Subject: Re: Size of horizontal loop? Date: 31 Jul 2006 09:14:00 -0700 Message-ID: <1154362440.123788.10630@s13g2000cwa.googlegroups.com> References: <4j1i51F5rquhU1@individual.net> Make the loop square and resonant on 80... Make a mechanical switch of some sort so you can open the loop opposite the feed point... This will make 160 meters easy to match, and may even be helpful on higher bands to change the direction of the main lobes... denny Article: 227485 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: effect of metal pipe supporting a vertical cage antenna Date: Mon, 31 Jul 2006 09:37:10 -0700 Message-ID: References: On Mon, 31 Jul 2006 08:12:41 -0400, David George Johnson wrote: >I want to put an eight wire vertical cage around a one hundred twenty >foot steel support for 80 meters. I can center feed the cage with >open wire line, which I assume will be more efficient than feeding the >steel at the bottom. Hi David, Certainly more complex as you would need to draw the feed off at right angles for some distance (a quarterwave or more). Do you have a second 60 foot tower at least that far away to string it out? As Denny's experience shows, nothing really to be gained (except the unstated bandwidth increase); and it could be done easier at ground level feeding the skirt wires that are all connected to the steel mast at the top. This cage is significantly larger than the mast diameter, isn't it? It should be, or you are wasting your time. >The cage will not be in contact with the ground That's fine. >or the tower. It should be, at the top, as stated above. >My thought is that the wires will make a better >radiator than the steel, but I have no idea what the steel "core" will >do to the efficiency of the antenna. I have had no success in >modelling this antenna. That is a fairly trivial task: select a sufficient "wire" diameter, and choose the loss of steel. In the end, for a fat wire, it won't matter much at the lengths and wavelength you are describing. >So my question is will the center fed, ungrounded cage dipole provide >any real advantage over feeding the tower at the bottom? Nope. 73's Richard Clark, KB7QHC Article: 227486 of rec.radio.amateur.antenna From: brettsbignose@hotmail.com Subject: Re: Antenna suggestion Date: 31 Jul 2006 09:41:14 -0700 Message-ID: <1154364074.412844.17970@h48g2000cwc.googlegroups.com> References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> > Is it possible that your radio power level is 1,000 m.w. rather than 1000 > m.a.? > It most certainly is 1000 m.A.! I must have been quite exhausted when I wrote that. > I think this 'antenna' problem can be easily/inexpensively solved. if the > location of the balloon is known. > The location of the balloon is not 'known'. I was hoping that you would not have to point the antenna in the general direction. Can you get an omnidirectional antenna? Thanks, Brett Article: 227487 of rec.radio.amateur.antenna From: brettsbignose@hotmail.com Subject: Re: Antenna suggestion Date: 31 Jul 2006 09:41:38 -0700 Message-ID: <1154364098.298137.20110@h48g2000cwc.googlegroups.com> References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Too heavy. :-) Irv Finkleman wrote: > brettsbignose@hotmail.com wrote: > > > > Sirs: > > > > I am a programmer and electrician, but not a radio person! I am > > sending an experimental balloon to over 100,000 ft. I have purchased > > two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of > > 1000 m.a., which states it will transmit and receive up to 20 miles > > line of sight. I do realize that this is probably under ideal > > circumstances and will not likely be the case when I actually deploy. > > I would be interested in purchasing some antennas which would somehow > > increase the range. What sort of characteristics make up a good > > antenna for what I want to do? It is possible that someone could find > > me one that would work with my project? Also, anything you might > > contribute concerning radio transmission would be very much > > appreciated. > > Money is no object for this experiment, so any ideas you have are very > > much welcome. > > > > Thanks, > > Brett > > How about a 100,000 ft trailing wire? > > Irv VE6BP > > -------------------------------------- > Visit my HomePage at http://members.shaw.ca/finkirv/index.html > Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm > Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm > -------------------- > Irv Finkleman, > Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP > Calgary, Alberta, Canada Article: 227488 of rec.radio.amateur.antenna From: brettsbignose@hotmail.com Subject: Re: Antenna suggestion Date: 31 Jul 2006 09:43:15 -0700 Message-ID: <1154364195.698865.180430@b28g2000cwb.googlegroups.com> References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> I must be cursed: Yes, the power output is 1000 milliwatts. Article: 227489 of rec.radio.amateur.antenna From: brettsbignose@hotmail.com Subject: Re: Antenna suggestion Date: 31 Jul 2006 09:45:06 -0700 Message-ID: <1154364306.233295.191790@b28g2000cwb.googlegroups.com> References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Yes, I did think of temperature concerns. The radio unit itself should be kept at above freezing if my calculations are correct. However, does the antenna need to be kept warm? Owen Duffy wrote: > On Fri, 28 Jul 2006 22:29:51 GMT, Owen Duffy wrote: > > > >>> sending an experimental balloon to over 100,000 ft. I have purchased > >>> two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of > >>> 1000 m.a., which states it will transmit and receive up to 20 miles > >>> line of sight. I do realize that this is probably under ideal > > I did mean to comment on the temperature spec for the radio. The > temperature in the troposhere can be as low at -50 to -75 deg C, will > the radio get cold enough in transit to fail (eg battery failure, > condensation etc). > > Owen > -- Article: 227490 of rec.radio.amateur.antenna From: "Roger Wiseman" Subject: Re: New No-code HF Pro-Technology Exam Date: Mon, 31 Jul 2006 12:50:15 -0400 Message-ID: References: The VE I blew for my ticket wouldn't like that very much. "V.E.C." wrote in message news:arrl.vec.sej0rf-sdofcvkw-sodkmv@arrl.vec... > > NO-CODER LICENSE APPLICATION and EXAM > > (Simplified test approved by all book and magazine publi$her$ and > VE whorehou$e$ who $ay "We need more ham$") > > Please PRINT (that means no squiggly lines) > > YOUR NAME (what they call you) > __________________________________________ > > ADDRESS (where you live) _______________________________________________ > > BIRTHDATE (when you were born) ________________________________ > > EXAM > > Instructions: Make a circle (one of these round things O ) around the > letter of the best answer! This is so we know what your answer to the > question is! > > 1. You TALK into a microphone with your _______. > > A. Hands > B. Feet > C. Toes > D. Mouth > E. Armpits > > 2. When you talk into a microphone, you talk into _______. > > A. the front > B. the back > C. the top > D. the bottom > E. the wire > > 3. "HEADPHONES" are worn over the ___________. > > A. Knees > B. Eyes > C. Toes > D. Ears > E. Lips > > 4. What do you do with the AC line cord coming out of a power supply? > > A. Hold it in the air to pick up signals > B. Pull on it to start the motor > C. Talk into the plug to get real "skip DX" > D. Hook it to your antenna > E. Insert the plug into a source of power > > 5. A "two meter" radio is: > > A. twice as strong as a one-meter radio > B. two one-meter radios in series > C. a CB with two meters on the front panel > D. a good doorstop > E. yo mama > > 6. A "ten-foot mast" is how long? > > A. Ten feet > B. Ten pounds > C. Two meters > D. Tree-top tall > E. yo mama > > 7. A "Triband antenna" is made to work on how many bands? > > A. 1 > B. 2 > C. 3 > D. 4 > E. 10 > > 8. The "Marconi" antenna is named after: > > A. Marconi > B. Mantovani > C. macaroni > D. Dean Martin > E. yo mama > > 9. What colors of DIODES can you buy at a Radio Shack store? > > A. Red, blue and black > B. Red, yellow and green > C. Orange and brown > D. I am colorblind so this is a discriminatory question and I should > automatically get my license because you have been mean to me. > E. I have no intention of ever using DIODES, so I should get my > license for free. > > 10. What color of SLURPEE can you buy at 7-11? > > A. Red, blue and black > B. Red, yellow and green > C. Orange and brown > D. I am colorblind so this is a discriminatory question and I should > automatically get my license and free slurpees forever because you > have been mean to me. > > END OF EXAM. > > YOUR SIGNATURE (slap yo tag here) > _________________________________________ > > Scoring: > > Get THREE correct and you get an EXTRA!!!! > Get TWO right and you get an ADVANCED!!!! > Get ONE right and you get a GENERAL!!! > Blow them all? Just blow the VE and get any license you want!!! Article: 227491 of rec.radio.amateur.antenna From: brettsbignose@hotmail.com Subject: Re: Antenna suggestion Date: 31 Jul 2006 09:59:54 -0700 Message-ID: <1154365194.062752.239140@m79g2000cwm.googlegroups.com> References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> Dave wrote: > At an altitude of 100,000 feet 1000 mw [1 watt] should reach to the radio > horizon of about 300 miles assuming a good receiver on the far end of the range. > Do you mean that I should be able to pick up a signal from 300 miles away??? I don't believe I understand the forces at work here. > A vertically polarized 1/2 wavelength antenna should work fine. At least it > would be my starting point. Second option would be an inverted [upside down] 1/4 > wavelength ground plane. Either antenna is not expensive. > I was hoping to only put an antenna on the vehicle that I chase the balloon with. It weighs too much to put it on the balloon itself. However, would it decrease my performance that much??? I asked this similar question to Aerocomm(who manufactures the radios). They sent me two possible antennas, but I'm not sure either is really what I want. http://www.coronaos.com/hg908y.pdf http://www.coronaos.com/hg908p.pdf > What information is to be transmitted? If you are looking for moderate speed > telemetry then a path loss versus error rate study needs to be done. If data is > being transmitted a gain antenna may be required at the receiver. Gain antennas > are not expensive and the antenna needs to be pointed at and follow the > balloon's flight path. > I'm not really sure how much data is transmitted. You need to check out the product description for these devices. From a programmer's perspective, I don't need to do any initializing of the radio. Whatever data I transmit out of the serial port is what shows up out of the other radio's serial port. Pretty basic. I am not planning to send images back, just little bits of data. But I would like the reliability of the connection to be such that I could send back a photo if I needed to. It would be nice if somebody could give me a link to a website where I could buy the proper antenna with a proper connector. Here is the e-mail from Aerocomm: You can try one of the antennas that I have attached information on. The panel offers better overall coverage while the yagi is more focused and covers longer distance. These are not officially approved for use by the FCC. Remember that the ConnexLink has a reverse polarity SMA jack for the antenna connector. Thanks for all the replies! Brett Article: 227492 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Reflection on Resistive loads References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> <12crrqrljfra196@corp.supernews.com> Message-ID: Date: Mon, 31 Jul 2006 17:10:54 GMT Cecil Moore wrote: > Roy Lewallen wrote: >> And, if you assume the line is lossless, the voltage and current are >> in phase every 90 degrees along the line regardless of the amount of >> mismatch. > > If the line has losses, the SWR circle becomes an SWR spiral > but the spiral still crosses the purely resistive axis like > the circle does, just not at the same points. > > Does your answer imply that the number of degrees between > purely resistive crossings is not equal to 90 degrees when > the line is lossy? (Not a trick question) After further thought, I think Roy's point is that a lossless transmission line has a purely resistive Z0 so the voltage and current are in phase every 90 degrees. Z0 is not purely resistive for ordinary transmission lines. But real-world distortionless lines are indeed lossy while possessing a purely resistive Z0. -- 73, Cecil http://www.qsl.net/w5dxp Article: 227493 of rec.radio.amateur.antenna Date: Mon, 31 Jul 2006 13:42:37 -0400 From: Dave Subject: Re: Antenna suggestion References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> <1154364306.233295.191790@b28g2000cwb.googlegroups.com> Message-ID: If the radio is the CL4790-1000 it is rated to -40C. For short term exposure to cold, have you considered a small thermal blanket? It is drawing 5 watts from the battery and power output is one watt. So, you have 4 watts of heat. Possibly enough for a small thermal blanket. Antenna should not require any heating element. brettsbignose@hotmail.com wrote: > Yes, I did think of temperature concerns. The radio unit itself should > be kept at above freezing if my calculations are correct. However, > does the antenna need to be kept warm? > > Owen Duffy wrote: > >>On Fri, 28 Jul 2006 22:29:51 GMT, Owen Duffy wrote: >> >> >> >>>>>sending an experimental balloon to over 100,000 ft. I have purchased >>>>>two 900MHz RF Aerocomm ConnexLink Radios. The radios have a power of >>>>>1000 m.a., which states it will transmit and receive up to 20 miles >>>>>line of sight. I do realize that this is probably under ideal >> >>I did mean to comment on the temperature spec for the radio. The >>temperature in the troposhere can be as low at -50 to -75 deg C, will >>the radio get cold enough in transit to fail (eg battery failure, >>condensation etc). >> >>Owen >>-- > > Article: 227494 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Antenna suggestion Date: Mon, 31 Jul 2006 10:59:33 -0700 Message-ID: References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> <1154365194.062752.239140@m79g2000cwm.googlegroups.com> On 31 Jul 2006 09:59:54 -0700, brettsbignose@hotmail.com wrote: >http://www.coronaos.com/hg908y.pdf >http://www.coronaos.com/hg908p.pdf Hi Brett, These are commercial antennas, the first is what you might use in your chase car. It exhibits gain from the complexity of its design. It also exhibits a sharp lobe that is inconsistent with use on a balloon (unless you add tracking servos - yeh, you are not going there). >It would be nice if somebody could give me a link to a website where I >could buy the proper antenna with a proper connector. If you have such a tight weight budget, you should be doing it yourself. Packaged products are always heavier. You "could" get away with a simple piano wire stinger stuck into the transmitter's jack. 73's Richard Clark, KB7QHC Article: 227495 of rec.radio.amateur.antenna Date: Mon, 31 Jul 2006 14:13:04 -0400 From: Dave Subject: Re: Antenna suggestion References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> <1154365194.062752.239140@m79g2000cwm.googlegroups.com> Message-ID: brettsbignose@hotmail.com wrote: > Dave wrote: > >>At an altitude of 100,000 feet 1000 mw [1 watt] should reach to the radio >>horizon of about 300 miles assuming a good receiver on the far end of the range. >> > > > Do you mean that I should be able to pick up a signal from 300 miles > away??? I don't believe I understand the forces at work here. > REDACTED YEP! Three hundred miles away IF ... IF the balloon is at 100,000 feet altitude!! The specs read "line of sight". At an altitude of 10,000 feet the radio line of sight horizon is about 120 miles. A typical UHF [900 MHz] receiver should be able to receive a signal as weak as 0.0000000000002 [2E-14] watts [1 uV] using a simple vertical antenna. Three hundred miles line of sight from 100,000 feet altitude is approximately 1.4E6 wavelengths. The power density at 300 miles from a 100,000 feet high balloon is approximately 8E-14 watts/wavelength^2 [2 uV]. The signal should be heard, but the noise margin is low for reliable digital data transmission. A gain antenna at the receiver will improve the signal to noise ratio significantly. The forces at work here are simply the receiving sensitivity of your earth bound receiver. Ham receivers have sensitivities less than 1 uV. The power divergence from the transmitter was assumed spherical for 1.4E6 wavelengths, and the receiver was assumed to have 1 uV sensitivity. > >>A vertically polarized 1/2 wavelength antenna should work fine. At least it >>would be my starting point. Second option would be an inverted [upside down] 1/4 >>wavelength ground plane. Either antenna is not expensive. Above is for the balloon. Below is for the chase vehicle. >> > > > I was hoping to only put an antenna on the vehicle that I chase the > balloon with. It weighs too much to put it on the balloon itself. > However, would it decrease my performance that much??? I asked this > similar question to Aerocomm(who manufactures the radios). They sent > me two possible antennas, but I'm not sure either is really what I > want. > http://www.coronaos.com/hg908y.pdf > http://www.coronaos.com/hg908p.pdf > REDACTED > Either antenna should do the job. The hg908Y would let you eyeball sight along the axis in the general direction of the balloon. Both are gain antennas. Article: 227496 of rec.radio.amateur.antenna From: ab2rc Subject: Re: New No-code HF Pro-Technology Exam References: Message-ID: Date: Mon, 31 Jul 2006 19:01:33 GMT On 2006-07-30, V.E.C. wrote: > > 1. You TALK into a microphone with your _______. > I don't use microphones, I am a digital operator. > 2. When you talk into a microphone, you talk into _______. > See above... > 3. “HEADPHONES” are worn over the ___________. > See above... > > 4. What do you do with the AC line cord coming out of a power supply? > > A. Hold it in the air to pick up signals > B. Pull on it to start the motor > C. Talk into the plug to get real "skip DX" > D. Hook it to your antenna > E. Insert the plug into a source of power > Usually E, but if you have about 17 feet of it you could use it to build a 20m dipole, so A or D is a possibility > 5. A “two meter” radio is: > D. a good doorstop D -- Unless you are using it for APRS > > 6. A "ten-foot mast" is how long? > > A. Ten feet > B. Ten pounds > C. Two meters > D. Tree-top tall > E. yo mama 120 inches > > 7. A “Triband antenna” is made to work on how many bands? > > A. 1 > B. 2 > C. 3 > D. 4 > E. 10 None of the above -- It will radiate on all bands, just better on 3 of them, so it depends on your defination of "works". > > 8. The “Marconi” antenna is named after: > Andrew Jameson's grandson > > 9. What colors of DIODES can you buy at a Radio Shack store? > Radio Shack does not sell diodes anymore.... > > 10. What color of SLURPEE can you buy at 7-11? > > A. Red, blue and black > B. Red, yellow and green > C. Orange and brown > D. I am colorblind so this is a discriminatory question and I should > automatically get my license and free slurpees forever because you > have been mean to me. red, green, blue, orange, yellow, brown, white and purple Article: 227497 of rec.radio.amateur.antenna From: "an old friend" Subject: Re: New No-code HF Pro-Technology Exam Date: 31 Jul 2006 12:03:20 -0700 Message-ID: <1154372600.728944.189240@i42g2000cwa.googlegroups.com> References: R. Scott wrote: > V.E.C. wrote: > > NO-CODER LICENSE APPLICATION and EXAM > > I bet you fought AM and SSB too. and CW itself (in favor of Spark) Article: 227498 of rec.radio.amateur.antenna From: fartabulous@gmail.com Subject: Ignorance Sucks! Date: 31 Jul 2006 12:40:17 -0700 Message-ID: <1154374816.969402.183150@m73g2000cwd.googlegroups.com> http://www.ignorancesucks.com Article: 227499 of rec.radio.amateur.antenna Date: Mon, 31 Jul 2006 15:41:12 -0400 From: Dave Subject: Re: New No-code HF Pro-Technology Exam References: Message-ID: AE +++++++++ Boy is he smart!!!!!! ab2rc wrote: > On 2006-07-30, V.E.C. wrote: > >>1. You TALK into a microphone with your _______. >> > > > I don't use microphones, I am a digital operator. > > > >>2. When you talk into a microphone, you talk into _______. >> > > > See above... > > >>3. “HEADPHONES” are worn over the ___________. >> > > > See above... > > >>4. What do you do with the AC line cord coming out of a power supply? >> >> A. Hold it in the air to pick up signals >> B. Pull on it to start the motor >> C. Talk into the plug to get real "skip DX" >> D. Hook it to your antenna >> E. Insert the plug into a source of power >> > > > Usually E, but if you have about 17 feet of it you could use it to build a > 20m dipole, so A or D is a possibility > > > >>5. A “two meter” radio is: >> D. a good doorstop > > > D -- Unless you are using it for APRS > > >>6. A "ten-foot mast" is how long? >> >> A. Ten feet >> B. Ten pounds >> C. Two meters >> D. Tree-top tall >> E. yo mama > > > 120 inches > > > > >>7. A “Triband antenna” is made to work on how many bands? >> >> A. 1 >> B. 2 >> C. 3 >> D. 4 >> E. 10 > > > None of the above -- It will radiate on all bands, just better on 3 of them, > so it depends on your defination of "works". > > > > >>8. The “Marconi” antenna is named after: >> > > > Andrew Jameson's grandson > > > >>9. What colors of DIODES can you buy at a Radio Shack store? >> > > > Radio Shack does not sell diodes anymore.... > >>10. What color of SLURPEE can you buy at 7-11? >> >> A. Red, blue and black >> B. Red, yellow and green >> C. Orange and brown >> D. I am colorblind so this is a discriminatory question and I should >>automatically get my license and free slurpees forever because you >>have been mean to me. > > > red, green, blue, orange, yellow, brown, white and purple > > > Article: 227500 of rec.radio.amateur.antenna Date: Mon, 31 Jul 2006 16:54:30 -0400 From: "J. D. B." Subject: Re: New No-code HF Pro-Technology Exam References: Message-ID: Somehow, this makes much more sense that a worthless CW exam. V.E.C. wrote: > NO-CODER LICENSE APPLICATION and EXAM > > (Simplified test approved by all book and magazine publi$her$ and > VE whorehou$e$ who $ay “We need more ham$”) > > Please PRINT (that means no squiggly lines) > > YOUR NAME (what they call you) > __________________________________________ > > ADDRESS (where you live) _______________________________________________ > > BIRTHDATE (when you were born) ________________________________ > > EXAM > > Instructions: Make a circle (one of these round things O ) around the > letter of the best answer! This is so we know what your answer to the > question is! > > 1. You TALK into a microphone with your _______. > > A. Hands > B. Feet > C. Toes > D. Mouth > E. Armpits > > 2. When you talk into a microphone, you talk into _______. > > A. the front > B. the back > C. the top > D. the bottom > E. the wire > > 3. “HEADPHONES” are worn over the ___________. > > A. Knees > B. Eyes > C. Toes > D. Ears > E. Lips > > 4. What do you do with the AC line cord coming out of a power supply? > > A. Hold it in the air to pick up signals > B. Pull on it to start the motor > C. Talk into the plug to get real "skip DX" > D. Hook it to your antenna > E. Insert the plug into a source of power > > 5. A “two meter” radio is: > > A. twice as strong as a one-meter radio > B. two one-meter radios in series > C. a CB with two meters on the front panel > D. a good doorstop > E. yo mama > > 6. A "ten-foot mast" is how long? > > A. Ten feet > B. Ten pounds > C. Two meters > D. Tree-top tall > E. yo mama > > 7. A “Triband antenna” is made to work on how many bands? > > A. 1 > B. 2 > C. 3 > D. 4 > E. 10 > > 8. The “Marconi” antenna is named after: > > A. Marconi > B. Mantovani > C. macaroni > D. Dean Martin > E. yo mama > > 9. What colors of DIODES can you buy at a Radio Shack store? > > A. Red, blue and black > B. Red, yellow and green > C. Orange and brown > D. I am colorblind so this is a discriminatory question and I should > automatically get my license because you have been mean to me. > E. I have no intention of ever using DIODES, so I should get my > license for free. > > 10. What color of SLURPEE can you buy at 7-11? > > A. Red, blue and black > B. Red, yellow and green > C. Orange and brown > D. I am colorblind so this is a discriminatory question and I should > automatically get my license and free slurpees forever because you > have been mean to me. > > END OF EXAM. > > YOUR SIGNATURE (slap yo tag here) > _________________________________________ > > Scoring: > > Get THREE correct and you get an EXTRA!!!! > Get TWO right and you get an ADVANCED!!!! > Get ONE right and you get a GENERAL!!! > Blow them all? Just blow the VE and get any license you want!!! Article: 227501 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: New No-code HF Pro-Technology Exam Date: Mon, 31 Jul 2006 16:04:59 -0500 Message-ID: <12css3r3v7gmb6@corp.supernews.com> References: Dave wrote: > AE +++++++++ > > Boy is he smart!!!!!! > No, it's "Yo he be smart" or "He are smart" > ab2rc wrote: > >> On 2006-07-30, V.E.C. wrote: >> >>> 1. You TALK into a microphone with your _______. >>> >> >> >> I don't use microphones, I am a digital operator. >> >> >> >>> 2. When you talk into a microphone, you talk into _______. >>> >> >> >> See above... >> >> >>> 3. “HEADPHONES” are worn over the ___________. >>> >> >> >> See above... >> >> >>> 4. What do you do with the AC line cord coming out of a power supply? >>> >>> A. Hold it in the air to pick up signals >>> B. Pull on it to start the motor >>> C. Talk into the plug to get real "skip DX" >>> D. Hook it to your antenna >>> E. Insert the plug into a source of power >>> >> >> >> Usually E, but if you have about 17 feet of it you could use it to >> build a >> 20m dipole, so A or D is a possibility >> >> >> >>> 5. A “two meter” radio is: >>> D. a good doorstop >> >> >> >> D -- Unless you are using it for APRS >> >> >>> 6. A "ten-foot mast" is how long? >>> >>> A. Ten feet >>> B. Ten pounds >>> C. Two meters >>> D. Tree-top tall >>> E. yo mama >> >> >> >> 120 inches >> >> >> >> >>> 7. A “Triband antenna” is made to work on how many bands? >>> >>> A. 1 >>> B. 2 >>> C. 3 >>> D. 4 >>> E. 10 >> >> >> >> None of the above -- It will radiate on all bands, just better on 3 of >> them, >> so it depends on your defination of "works". >> >> >> >>> 8. The “Marconi” antenna is named after: >>> >> >> >> Andrew Jameson's grandson >> >> >> >>> 9. What colors of DIODES can you buy at a Radio Shack store? >>> >> >> >> Radio Shack does not sell diodes anymore.... >> >>> 10. What color of SLURPEE can you buy at 7-11? >>> >>> A. Red, blue and black >>> B. Red, yellow and green >>> C. Orange and brown >>> D. I am colorblind so this is a discriminatory question and I should >>> automatically get my license and free slurpees forever because you >>> have been mean to me. >> >> >> >> red, green, blue, orange, yellow, brown, white and purple >> >> >> > Article: 227502 of rec.radio.amateur.antenna From: "Bob Agnew" References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> Subject: Re: Reflection on Resistive loads Message-ID: Date: Mon, 31 Jul 2006 15:09:11 -0700 > > So how does a 1/2WL piece of transmission line driving a > 50 ohm load wind up with the voltage and current in phase > no matter what the SWR? > -- If the characteristic impedance of the transmission line is 50 ohms, then there are no reflections; furthermore the current and voltage are in phase at every point along the line, There are no standing waves in this case. In fact it doesnt matter how long the line is as long as it is terminated in its charcteristic impedance. This case corresponds to the circle in the middle of the Smith Chart on which the impedance is constant. "Cecil Moore" wrote in message news:vEbzg.77880$Lm5.66394@newssvr12.news.prodigy.com... > Bob Agnew wrote: >> Just a nit: You said: >> >>> If there are reflections, the voltage >>> and current are in phase only every 1/4 wavelength. >> >> Actually, if there are reflections, the voltage and current ar NEVER in >> phase. c> 73, Cecil http://www.qsl.net/w5dxp Article: 227503 of rec.radio.amateur.antenna From: jgboyles@aol.com Subject: Re: Reflection on Resistive loads Date: 31 Jul 2006 15:40:38 -0700 Message-ID: <1154385638.375433.178110@b28g2000cwb.googlegroups.com> References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> Bob Agnew wrote: > > > > So how does a 1/2WL piece of transmission line driving a > > 50 ohm load wind up with the voltage and current in phase > > no matter what the SWR? > > -- > > If the characteristic impedance of the transmission line is 50 ohms, then > there are no reflections; furthermore the current and voltage are in phase > at every point along the line, There are no standing waves in this case. > > In fact it doesnt matter how long the line is as long as it is terminated in > its charcteristic impedance. This case corresponds to the circle in the > middle of the Smith Chart on which the impedance is constant. It doesn't matter what the characteristic impedance of the transmission line is as long as it is an electrical 1/2WL. As such, you can have reflections, feeding a 50 ohm resistive load, and the voltage and current will be in phase 1/2WL back fron the load. Antenna matching with transmission line transformers use different impedance transmission lines to wind up with a perfect match. 73 Gary N4AST Article: 227504 of rec.radio.amateur.antenna Date: Mon, 31 Jul 2006 18:46:22 -0400 From: Mike Coslo Subject: Re: Antenna suggestion References: <1154106089.650965.202870@b28g2000cwb.googlegroups.com> <1154364306.233295.191790@b28g2000cwb.googlegroups.com> Message-ID: brettsbignose@hotmail.com wrote: > Yes, I did think of temperature concerns. The radio unit itself should > be kept at above freezing if my calculations are correct. However, > does the antenna need to be kept warm? Hi Brett In most cases, the transmitter will be in an enclosure. I'm assuming that there will be an experiment package. Many who do this sort of thing will make the enclosure out of Styrofoam. Some actually use styro picnic coolers. For typical flight durations, the inefficiencies of the electronics equipment on board the payload (read waste heat) will make up for the nasty temps outside. I've seen some cases where there has actually been a temperature rise. The criteria is a well sealed insulating box. And no, the antenna itself does not need to be warm. Just seal off the exit port to keep internal heat from leaking out. Your watt should be sufficient power. At 100 kilofeet, you will reach more that you likely want to reach! I've seen propagation maps that show a single balloon repeater at these heights covering 1/3rd of the US. - 73 de Mike KB3EIA - Article: 227505 of rec.radio.amateur.antenna From: "Bob Agnew" References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> <1154385638.375433.178110@b28g2000cwb.googlegroups.com> Subject: Re: Reflection on Resistive loads Message-ID: Date: Mon, 31 Jul 2006 16:00:42 -0700 I haven't taught this subject at the University level for a few years now, so my terminology is a little rusty. VSWR = (1 + abs(rho))/(1 - abs(rho)) When the reflection coefficient rho is +/- 1 the VSWR is infinite. When rho = 0 the VSWR is 1:1. A VSWR of 1:1 corresponds to the unit circle at the center of the Smith Chart. wrote in message news:1154385638.375433.178110@b28g2000cwb.googlegroups.com... > > Bob Agnew wrote: >> > >> > So how does a 1/2WL piece of transmission line driving a >> > 50 ohm load wind up with the voltage and current in phase >> > no matter what the SWR? >> > -- >> >> If the characteristic impedance of the transmission line is 50 ohms, then >> there are no reflections; furthermore the current and voltage are in >> phase >> at every point along the line, There are no standing waves in this case. >> >> In fact it doesnt matter how long the line is as long as it is terminated >> in >> its charcteristic impedance. This case corresponds to the circle in the >> middle of the Smith Chart on which the impedance is constant. > > It doesn't matter what the characteristic impedance of the > transmission line is as long as it is an electrical 1/2WL. As such, > you can have reflections, feeding a 50 ohm resistive load, and the > voltage and current will be in phase 1/2WL back fron the load. Antenna > matching with transmission line transformers use different impedance > transmission lines to wind up with a perfect match. > 73 Gary N4AST > Article: 227506 of rec.radio.amateur.antenna From: jgboyles@aol.com Subject: Re: Reflection on Resistive loads Date: 31 Jul 2006 16:22:15 -0700 Message-ID: <1154388135.791852.73530@s13g2000cwa.googlegroups.com> References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> Bob Agnew wrote: > I haven't taught this subject at the University level for a few years now, > so my terminology is a little rusty. VSWR = (1 + abs(rho))/(1 - abs(rho)) > > When the reflection coefficient rho is +/- 1 the VSWR is infinite. When rho > = 0 the VSWR is 1:1. A VSWR of 1:1 corresponds to the unit circle at the > center of the Smith Chart. Hi Bob, I have never taught at the University level myself, this is an "Amateur" newsgroup. If you look at the Smith Chart, 1/2WL reflects back the identical load impedance, no matter the transmission line characteristic impedance (neglecting losses). If you have a 1/2WL 600 ohm line driving a 50 ohm load, then you have reflections (SWR), but at the source end, you see 50 ohms (V and I in phase). 73 Gary N4AST Article: 227507 of rec.radio.amateur.antenna From: ml Subject: Re: heliax vs lmr References: Message-ID: Date: Mon, 31 Jul 2006 23:22:46 GMT In article , Ed wrote: > The problem you are having comparing heliax to coax is that you are not > considering all the parameters. Loss is only one aspect. The biggest > difference between most coax and Heliax is physical construction. Heliax, > properly installed, with last 10 to even 20 years outdoors before it should > be replaced. Coax would deteriorate much much faster. Heliax is a much > more "sturdy" product and can also hold up to weather damage better than > coax. Being made with a sold jacket also adds to its shielding superiority > over most coaxial cables. > > For most ham use, You'll get the performance you need with coax type > cables and not need heliax.... plus your wallet will remain fatter, too. > ( I haven't even mentioned the high cost of connectors for Heliax, if you > purchase them new.) > > > Ed K7AAT lots of good tips everyone thanks much Article: 227508 of rec.radio.amateur.antenna From: "Bob Agnew" References: <1154057457.019523.86470@p79g2000cwp.googlegroups.com> <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> <1154385638.375433.178110@b28g2000cwb.googlegroups.com> <1154388135.791852.73530@s13g2000cwa.googlegroups.com> Subject: Re: Reflection on Resistive loads Message-ID: Date: Mon, 31 Jul 2006 16:30:21 -0700 > Hi Bob, I have never taught at the University level myself, this is an > "Amateur" newsgroup. If you look at the Smith Chart, 1/2WL reflects OK __ I won't post here anymore. I once was an Amateur when I was 14. I thought that I wanted to get back into the hobby now that I am retired. wrote in message news:1154388135.791852.73530@s13g2000cwa.googlegroups.com... > > Bob Agnew wrote: >> I haven't taught this subject at the University level for a few years >> now, >> so my terminology is a little rusty. VSWR = (1 + abs(rho))/(1 - >> abs(rho)) >> >> When the reflection coefficient rho is +/- 1 the VSWR is infinite. When >> rho >> = 0 the VSWR is 1:1. A VSWR of 1:1 corresponds to the unit circle at the >> center of the Smith Chart. > > Hi Bob, I have never taught at the University level myself, this is an > "Amateur" newsgroup. If you look at the Smith Chart, 1/2WL reflects > back the identical load impedance, no matter the transmission line > characteristic impedance (neglecting losses). If you have a 1/2WL 600 > ohm line driving a 50 ohm load, then you have reflections (SWR), but at > the source end, you see 50 ohms (V and I in phase). > 73 Gary N4AST > Article: 227509 of rec.radio.amateur.antenna From: Richard Clark Subject: Re: Reflection on Resistive loads Date: Mon, 31 Jul 2006 16:43:32 -0700 Message-ID: References: <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> <1154385638.375433.178110@b28g2000cwb.googlegroups.com> <1154388135.791852.73530@s13g2000cwa.googlegroups.com> On Mon, 31 Jul 2006 16:30:21 -0700, "Bob Agnew" wrote: >> Hi Bob, I have never taught at the University level myself, this is an >> "Amateur" newsgroup. If you look at the Smith Chart, 1/2WL reflects > >OK __ I won't post here anymore. I once was an Amateur when I was 14. >I thought that I wanted to get back into the hobby now that I am retired. Hi Bob, You as a prof. are not alone here. We have several, some still in the saddle, others retired, and all Hams. You and Gary are not wrong either, simply posting at cross purposes when the topic was sidelined into half wave lines, SWR, and a demand for an explanation for a problem that was never offered in the first place. This was a troll that bit you, not Gary. 73's Richard Clark, KB7QHC Article: 227510 of rec.radio.amateur.antenna From: "H. Adam Stevens, NQ5H" Subject: Re: Reflection on Resistive loads Date: Mon, 31 Jul 2006 19:35:45 -0500 Message-ID: <12ct8f1str83m5a@corp.supernews.com> References: <7Ymyg.12959$2v.5364@newssvr25.news.prodigy.net> <1154280473.831241.122890@p79g2000cwp.googlegroups.com> <1154385638.375433.178110@b28g2000cwb.googlegroups.com> <1154388135.791852.73530@s13g2000cwa.googlegroups.com> "Richard Clark" wrote in message news:q35tc2pkcgr46dilimhoju7n2ptcb2tdin@4ax.com... > On Mon, 31 Jul 2006 16:30:21 -0700, "Bob Agnew" > wrote: > >>> Hi Bob, I have never taught at the University level myself, this is an >>> "Amateur" newsgroup. If you look at the Smith Chart, 1/2WL reflects >> >>OK __ I won't post here anymore. I once was an Amateur when I was 14. >>I thought that I wanted to get back into the hobby now that I am retired. > > Hi Bob, > > You as a prof. are not alone here. We have several, some still in the > saddle, others retired, and all Hams. You and Gary are not wrong > either, simply posting at cross purposes when the topic was sidelined > into half wave lines, SWR, and a demand for an explanation for a > problem that was never offered in the first place. This was a troll > that bit you, not Gary. > > 73's > Richard Clark, KB7QHC I have been an amateur continuously since I was 13: 1963. Transmission line: 1/2 half wave repeats the load, 1/4 wave inverts the load. That I knew in Jr High. Finally understood it when I studied E&M in college. 73 H. NQ5H www.hep.utexas.edu/mayamuon Article: 227511 of rec.radio.amateur.antenna From: mcalhoun@ksu.edu Subject: Re: neighborhood antenna restrictions Date: 31 Jul 2006 20:53:18 -0500 Message-ID: References: <1153692686.342597.27820@h48g2000cwc.googlegroups.com> <7q8gc29rlrk7j0lbrkttk8arlljkcbc9ot@4ax.com> <7C8zg.12390$lv.8869@fed1read12> >I also remeber the Scratchfasti Hatchi column in QST in the 50's! I read one of those columns at my local ham club several years ago, and the PC (Political Correctness) crowd practically threw me out on my ears! (But I still enjoy reading them!) -- --Myron A. Calhoun. Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge NRA Life Member W0PBV "Barbershop" tenor CDL(PTXS) (785) 539-4448 Certified Instructor (KS Concealed Carry, Rifle, Pistol, Home Firearm Safety) Article: 227512 of rec.radio.amateur.antenna From: "Frank's" References: <1bOdnTnoDO8PslzZRVnyuA@bt.com> <2_OdnX7zdY6gVFzZRVny3w@bt.com> <4jqxg.170368$771.62308@edtnps89> <_FCxg.133334$A8.100770@clgrps12> Subject: Re: Radiating Efficiency Message-ID: Date: Tue, 01 Aug 2006 02:23:45 GMT > Go back to program Radial_3 for a few minutes and insert our standard > inputs. > > Set the number of radials equal to One. > > Slowly vary length between 1 and 10 metres while observing Rin + jXin > of the radial system. > > Vary length to find maxima and minima in the value of Rin. Max and > min are more pronounced at the shorter lengths due to lower > attenuation. > > Remember, the radial ( transmission line ) is open-circuit at the > other end. > > There is a minimum of Rin when the radial is 1/4-wave resonant at 2.4 > metres. > > There is a maximum of Rin when the radial is 1/2-wave resonant at 4.8 > metres. > > There is another minimum of Rin, but less prominent, when the radial > is 3/4-wave resonant at 7.3 metres. > > As length and attenuation along the line increase, the variations of > Rin about its mean become smaller. Eventually, of course, it converges > on Ro, the characteristic impedance. ( Ro is also computed but > remains constant as length is varied.) > > There would be a full-wave resonance at approximately 10 metres but it > is damped-down into the noise by the attenuation of about 20 dB at > that length. > > Now, what I would like you to do is search for the maxima and and > minima in Rin, with their lengths. using NEC4. At some places you may > have to use increments of 0.1 metres. > > If you find any max and minima the values of Rin + jXin will be > different from my program and the lengths at which they occur may also > differ. I would like to use the information to improve the accuracy > of my program on the assumption that NEC4 is more correct when > calculating buried radials. > > ( In this investigation, you may think it peculiar that lengths as > small as 0.1 metres should be significant at 8 MHz. This is due to > the very low velocity of propagation along buried radials. Program > Radial_3 estimates VF.) Reg, I have done some computations around a 2 m radial length. I noticed that I had made an error in my previous calculation at exactly 2 m. 1.8 m -- Radial Z = 70.17 - j 24.1 1.9 m -- Radial Z = 68.5 - j 19.0 2.0 m -- Radial Z = 67.2 - j 14.2 2.1 m -- Radial Z = 66.2 - j 9.5 2.2 m -- Radial Z = 65.5 - j 5.0 2.3 m -- Radial Z = 65.1 - j 0.6 2.4 m -- Radial Z = 65.0 + j 3.6 2.5 m -- Radial Z = 65.2 + j 7.8 2.6 m -- Radial Z = 65.6 + j 11.7 I can keep going if you think that these are the results you expected. I am tempted to continue, in steps of 0.1 m, and plotting the results on the Smith Chart. I expect the data to rapidly spiral to the center of a chart normalized at 101. 6 ohms. Frank