Article: 221105 of rec.radio.amateur.antenna From: ml Subject: Re: Amoskeag Lightning Arrestor Questions References: Message-ID: Date: Thu, 19 Jan 2006 00:48:52 GMT Sorry your email address dosn't work but thanks for clarifing the hookup i must have missread the original statement you made whereby i thought you said the pro was completely disco i totally understand if it had anything connected that explains it!! however you confused me more so, now that you said the pro getting fried somehow 'saved' your other gear from being damaged... i can't see how that happened unless you feel the rig it self actually absorbed ALL the energy i presume the odds of that are slim so can you help unconfuse me?? and it was great to read about how the mil does stuff pretty cool again sorry about your damage hope you had arrl rig insurrance m In article , Amos Keag wrote: > ml wrote: > > > Hi > > > > FYI, seems your email addr here dosn't work, if it's a real one > > > > Dear Amos > > > > i saw your post and hope you wouldn't mind if i asked you a quick > > quesiton > > > > > > Your Icom that was damaged, was unplugged from everything so how did > > lightning 'get to it'?? > > > > I was kinda distrubed trying to figure it out > > \ > > Ground Loop. Took time to find it though. > > The Astron RS-35 power supply connects utility power neutral to the > case. It also connects the 13.8 volt return to the case. [This is > commercial common practice but is prohibited in Military Systems > design.] Although everything on the operating table was isolated from > the utility power and external antennas, everything was connected > together by coax braid, connections to the operating position common > 'ground', and the 13.8 volt return. > > Remember, this strike caused large area damage. Close to 50 homes > suffered some damage. Several homes took up to 6 weeks to have their > internet functioning again. > > The lightning strike tripped all [ALL] ground fault interruptors in the > house. The ground loop in my system connected chassis and power returns > and coax cable together. The weak link were circuit boards in my 756 Pro > II filter and tuner. The boards VAPORIZED. Smoke all over the place. > Pungent smell, etc. That failure protected my IC-746, Kenwood TM-G707, > etc from damage. [Expensive fuse!!] > > I wonder if it also protected my swimming pool pump and heater from > damage ? Article: 221106 of rec.radio.amateur.antenna From: "Asimov" Subject: Re:Amoskeag Lightning Arrestor Questions Message-ID: References: <19272-43CE864F-1277@storefull-3255.bay.webtv.net> Date: Thu, 19 Jan 2006 01:01:28 GMT "Richard Harrison" bravely wrote to "All" (18 Jan 06 12:17:51) --- on the heady topic of "Re:Amoskeag Lightning Arrestor Questions" RH> From: richardharrison@webtv.net (Richard Harrison) RH> Xref: core-easynews rec.radio.amateur.antenna:222822 RH> Asimov wrote: RH> "An acquaintance had a direct hit on his tower and even his tv`s RH> remote control head." There seems to be a problem with the compression. I wrote "remote control fried." not "head."! RH> Did he hear a voice boom from the clouds saying: "Dammit! Missed RH> again!"? RH> A good tower ground should mitigate lightning`s fiversion through a TV What is a "fiversion"... ah "diversion", right! Damn that compressor is F&^^%$@@** RH> remote control. But, I`ve seen stories of "ball lightning" chasing RH> about inside a house. That is what he said. Briefly saw a fireball wizz around the room. A*s*i*m*o*v Article: 221107 of rec.radio.amateur.antenna From: "Jerry" References: <11rr4922agp1acd@corp.supernews.com> <1sYwf.5083$fb4.758@newssvr14.news.prodigy.com> Subject: Re: WTB Outbacker Mobile HF Antenna Message-ID: Date: Wed, 18 Jan 2006 20:37:20 -0500 "Mike Coslo" wrote in message news:Ge2dneQFMt0b8FXeRVn-hw@adelphia.com... > Jerry wrote: >> "kd5sak" wrote in message >> news:Qjixf.119$H71.20@newssvr13.news.prodigy.com... >> >>>"Bill Turner" wrote in message >>>news:dq498d016ak@enews4.newsguy.com... >>> >>>>ORIGINAL MESSAGE: >>>>I used to think that way too. Only bought the cheap stuff until one day >>>>someone gave me a bottle of Glenlivet scotch. I rarely buy it because I >>>>don't want to mortgage the house, but now I *do* know the difference. >>>>:-) >>>> >>>>Bill, W6WRT >>>> >>>> >>> >>>Have to agree, bought some really high dollar Scotch for New Years Eve in >>>1954 while in Japan. Flavor wasn't the same but it was as smooth as >>>chocolate milk. I was asleep before midnight. Had to quit that sort of >>>thing though, my Dad was alcoholic and I figured I'd probably inherited >>>the gene. >>> >>>Harold Burton >> >> >> That's just it for me. I don't want to run the risk, and after seeing >> what it did to friends and relatives as well, it made up my mind in high >> school. Tried it. It tasted AWFUL no matter what, so I prefer a Coke. Oh, >> if someone insists I take a sip with him, I will. But since I simply do >> not like the taste of alcoholic drinks, I simply drink enough to satisfy >> the buyer and let it go. I just don't like it the same way some people >> don't like broccoli or cauliflower and I never will. :) > > > Well good for you if you don't like Little John Barleycorn. But I find it > ironic that you consider that cola beverages taste good. I always > considered them as probably what carbonated battery acid tastes like. > > And the caffeine in them is also a drug, of which a lot of people take too > much of. > > - 73 de Mike KB3EIA - > > ..... at this time sipping on small glass of Akvavit.... What? You mean I have to give up coffee, too? LOL! 73 J Article: 221108 of rec.radio.amateur.antenna From: dplatt@radagast.org (Dave Platt) Subject: Re: Amoskeag Lightning Arrestor Questions Date: Thu, 19 Jan 2006 06:41:33 -0000 Message-ID: <11sud4trs50t074@corp.supernews.com> References: <11st5vd8qeie574@corp.supernews.com> In article , Amos Keag wrote: >Maybe my terms are not up to date. > >My electrical service connection is 3 wire 240 volts AC at 60 Hz. Within >the distribution panel RED is connected to one feed; BLACK is connected >to the other feed and white is connected to the common connection >[return]. The common connection is then distributed throughout the house >as the bare wire in standard wiring. The common, white and return, >connection is connected to an external earth connection [ground] by an 8 >foot ground rod.. So, the WHITE wire serves as return for both RED and >BLACK circuits and has a single earth connection. So, your 3 prong >socket contains connections to power as follows: HOT [either RED or >BLACK] circuit, RETURN [WHITE] and GREEN [GROUND] [supposedly zero >current carrying. A GFI works on this part of the connection]. > >In the ASTRON RS 35 the primary wiring has the GREEN connected to the >chassis. The BLACK/WHITE go to the transformer primary. This is fine. Yes, that's all fine, and per code. In US wiring terminology, the green wire is "ground". It's present entirely for safety purposes - it's not supposed to carry any current back to the panel during normal operation. It carries current only in the event of a fault. It's what the external chassis should be tied to, for metal-chassis equipment with a three-wire cord. Black is "hot". I'm told that this color was chosen because black is traditionally the color of death. White is "neutral". It's the current return for the hot supply. It should never be tied to the chassis, for two reasons: [1] The occasional hot/ground reversal thanks to an mistake in the house wiring. You really don't want your chassis floating at 120 VAC above local ground. [2] The neutral pin at the outlet can be pulled several volts above ground voltage, if some load on that circuit is drawing a healthy number of amperes, due to I^2*R drop in the house wiring. If the chassis were tied to neutral, and this occurred, someone might manage to get a shock if they touched both the chassis and a truly-grounded pipe or wire. >With a nearby lightning strike that blew the utility 3 phase transformer >and affected approximately 50 consumers there are several possible >causes of trouble. Among these are imbalance in utility service [i.e. >the 240 into the house becomes seriously imbalanced] a lightning induced >magnetic transient that couples to all ground loops, or my system was >still connected to antennas and power. > >I had ALL connections to antennas and power plugs removed except the 1/2 >inch copper pipe earth connection at the service panel. My neighbors >lost garage door openers, multiple tv sets, numerous telephone circuits, >numerous internet circuits, COMCAST had to rewire approximately 1/4 mile >of cable tv in front of the house, several homes lost expensive stereo >and sound lab setups. In my house all ground fault interuptors >activated. And two circuits in my PRO II exploded to charcoal with dust >and stench. The LAN blew up, and one computer was lost. Ouch! My condolences! When a strike of that magnitude occurs nearby, I have a feeling that the Law of Chaos prevails. The current will do whatever it (censored) well wants to. Even some equipment which is entirely unplugged might take enough of a pulse via induction to suffer some damage to sensitive components. Glad to hear that you managed to recover the cost of replacement! -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! Article: 221109 of rec.radio.amateur.antenna From: "Robert11" Subject: Lightning Arrestor & Protection Of Receiver ? Date: Thu, 19 Jan 2006 07:52:38 -0500 Message-ID: Hello: Very interesting comments on my question of a few days ago re lightning arrestors. Thank you all for trying to educate me on this subject; really find it confusing. Thread is a bit buried by now, so thought I'd start another one. I fully understand that the best approach is to (also) just disconnect everything. But if not around, here's what I don't understand and concerns me. Assuming a "nearby" strike, and a subsequent emp pulse that's picked up by a receive only antenna wire strung outside: No matter how quickly an arrestor's gas tube fires, and diverts the pulse to a good RF ground, the fact that it takes a few hundred volt threshold to fire makes "any" gas tube type of arrestor almost worthless re the protection of a receiver whose front end certainly won't take a few hundred volts, even for u-seconds, probably. Do you agree with this statement, or am I missing something ? Thanks, Bob Article: 221110 of rec.radio.amateur.antenna From: Bob Miller Subject: Re: HF-Ground Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Date: Thu, 19 Jan 2006 14:38:29 GMT On 19 Jan 2006 06:04:29 -0800, john.minkjan@gmail.com wrote: >Question: > >Is you are making a HF-ground (radials just below the surface) Should >these radials be insulated or not? > >73 John In one of my antenna books, by W6SAI, he recommended uninsulated wire for buried radials. bob k5qwg Article: 221111 of rec.radio.amateur.antenna From: "John, N9JG" References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Subject: Re: HF-Ground Message-ID: Date: Thu, 19 Jan 2006 15:00:32 GMT To cut down on copper corrosion, I use enameled #14 magnet wire. "Bob Miller" wrote in message news:gk8vs15alefmq1i29mlr6i8pad4j9304du@4ax.com... > On 19 Jan 2006 06:04:29 -0800, john.minkjan@gmail.com wrote: > >>Question: >> >>Is you are making a HF-ground (radials just below the surface) Should >>these radials be insulated or not? >> >>73 John > > In one of my antenna books, by W6SAI, he recommended uninsulated wire > for buried radials. > > bob > k5qwg Article: 221113 of rec.radio.amateur.antenna From: "Bill Turner" Subject: Re: HF-Ground Date: 19 Jan 2006 16:28:53 GMT Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> john.minkjan@gmail.com wrote: > Question: > > Is you are making a HF-ground (radials just below the surface) Should > these radials be insulated or not? > > 73 John ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Insulated will reduce corrosion. Don't bury them any deeper than necessary. Lying on top of the ground is better. Dirt is not a good antenna element. Bill, W6WRT Article: 221114 of rec.radio.amateur.antenna From: fmmck@aol.com (Fred McKenzie) Subject: Re: FS: Heathkit Manuals Date: Thu, 19 Jan 2006 14:36:44 -0500 Message-ID: References: <9clis15i74n2k362ccco25fomq0nkr55h8@4ax.com> <43ca251a$0$36837$dbd43001@news.wanadoo.nl> <4303qhF1kq9u9U1@individual.net> In article <4303qhF1kq9u9U1@individual.net>, Reinhard Zwirner wrote: > > good that these stuff is available from half a dozen sites for free... > > Where? > > Very interested Reinhard- I was hoping someone would answer. These sites may not be what you're looking for but contain some references to Heath. Check out: http://www.circuitarchive.co.uk/heath.htm http://bama.sbc.edu/ http://www.d8apro.com/heath1.htm http://www.mods.dk/ 73, Fred, K4DII Article: 221115 of rec.radio.amateur.antenna From: "Tom the Canuck" References: Subject: Re: How to earn money with PAYPAL!!!! 37 Message-ID: Date: Thu, 19 Jan 2006 14:26:12 -0500 "JJSomar" wrote in message news:dqoe9l$2ig$1@news.uni-paderborn.de... > Paypal Magic !!!!! Earn ?5000 within 2 weeks with ease!!!!!. > > > Read this message until the end, and you will find out how the money flows in easy !!!!. > Follow the steps and it WILL work. Trust me !!!!!. > > It's NOT illegal and it is NOT a scam !!!!!. > It's *nice* to see another sucker join the bottom of the pyramid scheme. I wonder when the structure will collapse . . . . Tom the Canuck. Article: 221116 of rec.radio.amateur.antenna Date: Fri, 20 Jan 2006 06:43:42 +1000 From: Kev Subject: Re: Dick Smith Radio Direction Finder - Docs now in PDF References: <43C15BA4.3F39@orcon.net.nz> <43C98DF6.2958@orcon.net.nz> <43CF18B0.70E8@orcon.net.nz> Message-ID: <43cff9fe$0$10954$afc38c87@news.optusnet.com.au> Glenn McAllister wrote: > Scanned and kindly converted to PDF by Ken, ZL1WKT. > > Hosted by Al at > http://www.webdingers.com/K6345RadioDirectionFinder.pdf > and also by me at > http://www.freewebs.com/cqdx/dserdfk6345.htm > > Glenn McAllister wrote: > >>My email address is my callsign at orcon dot net dot enn zed >> >>de Glenn ZL2TLD Fantastic Thanks for doing that Now at least I can see what's what in this thing Cheers Kev Article: 221117 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: HF-Ground Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Date: Thu, 19 Jan 2006 21:05:58 GMT On 19 Jan 2006 16:28:53 GMT, "Bill Turner" wrote: >john.minkjan@gmail.com wrote: > >> Question: >> >> Is you are making a HF-ground (radials just below the surface) Should >> these radials be insulated or not? >> >> 73 John >~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > >Insulated will reduce corrosion. Don't bury them any deeper than >necessary. Lying on top of the ground is better. Dirt is not a good >antenna element. Bill, I often see the assertion that it is better to not bury radials. Can you point me to any reputable texts or experimental evidence that shows the difference between shallow buried radials and radials lying "on top of the ground"? Corrosion is often cited as a reason to use insulated buried radials, but is corrosion a significant risk in most locations. We widely use buried copper water pipes here, and copper clad earthing electrodes for the MEN power supply earthing, yet they don't seem to suffer significant corrosion in most places. It seems to me that insulated buried radials are likely to be less effective in a lightning protection role. Owen -- Article: 221118 of rec.radio.amateur.antenna From: Allodoxaphobia Subject: Re: what are Microwave Antennas? Date: 19 Jan 2006 21:13:12 GMT Message-ID: References: <1137700291.373977.273720@g44g2000cwa.googlegroups.com> On 19 Jan 2006 11:51:31 -0800, Bug3 wrote: > Wondering what are microwave antennas, what do they do, how do they > work, etc? > Are they used in wirless laptops, etc.? > I can use a lot of information on this subject, I have to wirte 3 or 4 > pages on this and don't really know much about them need to read as > much as possible. Just send me your teacher's email address and I'll submit the report directly. Also, send me your English teacher's email address. You'll find the world's biggest freakin' FAQ site here: http://www.google.com/search?as_epq=microwave+antenna Article: 221119 of rec.radio.amateur.antenna Subject: Re: HF-Ground From: Dave Oldridge References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Message-ID: Date: Thu, 19 Jan 2006 21:22:26 GMT "Bill Turner" wrote in news:xn0ehew7u3qjhj000 @cnews.newsguy.com: > john.minkjan@gmail.com wrote: > >> Question: >> >> Is you are making a HF-ground (radials just below the surface) Should >> these radials be insulated or not? >> >> 73 John > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Insulated will reduce corrosion. Don't bury them any deeper than > necessary. Lying on top of the ground is better. Dirt is not a good > antenna element. Electric fence wire is adequate and cheap. I use it right on the surface, as you say. It's a bit springy so you may have to work it to straighten it, though. -- Dave Oldridge+ ICQ 1800667 Article: 221120 of rec.radio.amateur.antenna From: "John, N9JG" References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Subject: Re: HF-Ground Message-ID: Date: Thu, 19 Jan 2006 21:55:58 GMT Ok, but do you use steel or aluminum fence wire? Galvanized steel fence wire will rust in a few years. "Dave Oldridge" wrote in message news:Xns9750880B39C41doldridgsprintca@64.59.135.159... > > Electric fence wire is adequate and cheap. I use it right on the surface, > as you say. It's a bit springy so you may have to work it to straighten > it, though. > > -- > Dave Oldridge+ > ICQ 1800667 Article: 221121 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> Subject: Re: How to earn money with PAYPAL!!!! 37 Date: Thu, 19 Jan 2006 17:36:25 -0500 Message-ID: Now this is not a scam, simply send $1.00 from your paypal to w4jle@w4jle.com. I won't do anything for you, you will get nothing in return, and if I get enough suckers to bite I will go to OUTBACK Steak House and enjoy a meal on you. At least you know this won't cost more than a dollar, you need not worry about getting screwed, I have already told you up front you are. So get your guarenteed low cost screw job today! wrote in message news:1137709653.497618.151660@o13g2000cwo.googlegroups.com... > Tom, realize that many newsgroup readers are so young that they are not > familiar with the Ponzi scam. Otherwise they would not buy programs > that perpetuate the scheme (or scam). > > http://home.nycap.rr.com/useless/ponzi/ > > Harry C. > Article: 221122 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> Subject: Re: How to earn money with PAYPAL!!!! 37 Date: Thu, 19 Jan 2006 18:00:33 -0500 Message-ID: Of course, Seniors over 55 may get their guarenteed screwing fo $.90 a whopping 10% discount, again send your payment to w4jle@w4jle.com DO IT TODAY! This offer may end at any time... "GBrown" wrote in message news:XP-dnbRl__AZiE3enZ2dnUVZ_t-dnZ2d@gwi.net... > Do I get a seniors discount? > . > . > . > "Fred W4JLE" wrote in message > news:d51a1$43d01476$471d24c1$14966@ALLTEL.NET... > > Now this is not a scam, simply send $1.00 from your paypal to > > w4jle@w4jle.com. I won't do anything for you, you will get nothing in > > return, and if I get enough suckers to bite I will go to OUTBACK Steak > House > > and enjoy a meal on you. > > > > At least you know this won't cost more than a dollar, you need not worry > > about getting screwed, I have already told you up front you are. So get > your > > guarenteed low cost screw job today! > > > > wrote in message > > news:1137709653.497618.151660@o13g2000cwo.googlegroups.com... > > > Tom, realize that many newsgroup readers are so young that they are not > > > familiar with the Ponzi scam. Otherwise they would not buy programs > > > that perpetuate the scheme (or scam). > > > > > > http://home.nycap.rr.com/useless/ponzi/ > > > > > > Harry C. > > > > > > > > > Article: 221123 of rec.radio.amateur.antenna From: "SINYpyro" <*removethis*vanquish@earthlink.net> References: Subject: Re: How to earn money with PAYPAL!!!! 37 Message-ID: Date: Thu, 19 Jan 2006 23:21:27 GMT Kill yourself? "JJSomar" wrote in message news:dqoe9l$2ig$1@news.uni-paderborn.de... > Paypal Magic !!!!! Earn ?5000 within 2 weeks with > ease!!!!!. > > > Read this message until the end, and you will find out how the money flows > in easy !!!!. > Follow the steps and it WILL work. Trust me !!!!!. > > It's NOT illegal and it is NOT a scam !!!!!. > > > The only thing you need is : - E-MAIL ACCOUNT > - PREMIER (FREE) or BUSINESS PAYPAL ACCOUNT > - ?5 on this account (The only investment) > - 30 minutes of your time > > There is no limit on how much money you can recieve, and you haven't got > anything to lose with this Business program. I will explain how it works > !!!!!. > > > Follow these 4 easy steps and it WILL work !!!!!. > > > STEP 1 : SIGN UP FOR A FREE PAYPAL ACCOUNT !!!!!. > > Paypal is a free and safe way to pay and receive money on the > Internet. > Creating a account is as easy as creating a MSN account. > Copy and paste the next line in your Internet browser and sign up. > HTTP://WWW.PAYPAL.COM > > Be sure to sign up for a FREE Premier or Business account and not > for > a Personal account. You cannot receive CREDITCARD payments with > a Personal account and we can't have that. Do we !!!!!. > > > STEP 2 : SENT ?5 TO YOUR PAYPAL ACCOUNT > > This is your only investment to receive the money with ease. > > With your Paypal account, send ?1 to each e-mailadres listed > below. > !!!!! IMPORTANT !!!!! Be sure to use this SUBJECT : *PLEASE PUT ME > ON > YOUR EMAIL LIST* when you send the money. > > 1) dexxatol@netcourrier.com > 2) armygirl8568@hotmail.com > 3) bovenpietje@hotmail.com > 4) tjoewonli@hotmail.com > 5) jjsomar@gmx.de > > > STEP 3 : PUT YOUR E-MAILADRES ON THE LIST > > After you have send ?1 to each e-mailadres, put your e-mailadres > on the > 5th place. Remove e-mailadres number 1, and move each e-mailadres > 1 > step up the ladder. !!!!! IMPORTANT !!!!! BE SURE THAT THE > E-MAILADRES > YOU USE IS THE SAME AS YOU USED TO SIGN UP AT PAYPAL. > > Remember that this is LEGAL. You are creating a service : an > e-mail > servicelist. > > > STEP 4 : UPLOAD OR COPY THIS MESSAGE TO NEWSGROUPS, FORUMS ETC > > There are 32.000 newsgroups. Upload or copy this message to at > least > 200 newsgroups or forums etc, but remember that the more your > upload > the more people will see your message and the MORE MONEY WILL FLOW > IN. > > How to upload to newsgroups and forums? : > > After you have followed step 1,2,3 and 4, save this message (and > copy > so you can use it again). Use your Internet browser and Outlook > Express > or another newsreader and try to find FORUMS, NEWSGROUPS, BULLETIN > BOARDS, DISCUSSION GROUPS, CHAT SITES and ONLINE COMMUNITIES. Use > GOOGLE or use a NEWSERVER. Use every option to post this message. > Download PostXpert to send 1 message to more NEWSGROUPS at the > same time. > > !!!!! REMEMBER !!!!! The more you post this message the more MONEY WILL > FLOW IN. > > > Why does this Business program work so well !!!!!. > > Lets asume that from the 200 (or more) messages that you have posted, only > 5 > people respond, you will have your ?5 back that you have invested. Those 5 > people will each send at least 200 messages with your e-mailadres on > number 4. > That's 5 x 5 x ?1 = ?25. The next 25 people will also send 200 messages > with > your adres on number 3. That's 25 x 5 x ?1 = ?125. The next 125 people > also send > 200 messages with your name on number 2. That's 125 x 5 x ?1 = ?625. Those > 625 > people again also send 200 messages with your name on number 1. That will > give > us a total off 625 x 5 x ?1 = ?3.125. This is only a EXAMPLE with 5 > reactions. > You WILL get MORE responses than that. > > Remember that most newsservers will leave the posted messages on there > servers > for about 2 weeks. If you will post your message again, it WILL again > start > from the beginning. So you can repeat this over and over again. > > Everyday MILLIONS of people are ONLINE and reading these messages, JUST > LIKE > YOU RIGHT NOW. I also was sceptical in the beginning and have read a lot > of > these messages. I also thought that it was bullshit. Until I thought : > What the > hell!, only ?5. What's ?5 and a couple of minutes of my time to solve my > money > problems. > > !!!!! REMEMBER !!!!! Follow every step, and IT WILL WORK, TRUST ME. !!!!! > > > > !!!!! BEST WISHES AND GOOD LUCK !!!!! > > > > > Article: 221124 of rec.radio.amateur.antenna From: - exray - Subject: Re: How to earn money with PAYPAL!!!! 37 Date: Thu, 19 Jan 2006 19:28:05 -0400 Message-ID: <11t0847nt2gj29a@corp.supernews.com> References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> Fred W4JLE wrote: > Now this is not a scam, simply send $1.00 from your paypal to > w4jle@w4jle.com. I won't do anything for you, you will get nothing in > return, and if I get enough suckers to bite I will go to OUTBACK Steak House > and enjoy a meal on you. > > At least you know this won't cost more than a dollar, you need not worry > about getting screwed, I have already told you up front you are. So get your > guarenteed low cost screw job today! Sounds like a scam to me! What if I send you a dollar and insist on medium rare and the next guy who sends a dollar wants well-done? Are you going to decide? Will you be sending our money back? Sorry, I see this as only leading to problems. I'm not falling for it. -Bill Article: 221126 of rec.radio.amateur.antenna From: John Ferrell Subject: Re: Starting point for antenna design Message-ID: References: <1qncs191l12sktnafsutgk2oh8qnpo6jdb@4ax.com> Date: Fri, 13 Jan 2006 15:11:39 GMT You miss my motives! I have a Cushcraft A4 beam that works very well with my Ten Tec Pegasus transceiver (inboard LDG tuner). In my eyes it is the perfect rig! I am not breaking any new ground. I am simply doing the lab exercise of validating the EZNEC calculations. I may find it worthwhile to drop to an 8-foot radiator and higher (10-Meters?) for ease of construction. The principal area of interest is in radiators less than 1/4 wave in length. At the moment, I am especially interested in the different feed arrangements. I am starting with the "Gotham" style of a single base loading coil and minimal radials then I plan on an autotransformer arrangement. I have a fair amount of room, a lot of scrap metal and wire is cheap! The principal limitations are time and my level of intellect... Staying on track will be a problem, moving the load up the radiator is already looking appealing! On Thu, 12 Jan 2006 15:14:32 GMT, Cecil Moore wrote: >John Ferrell wrote: >> My current project is "What can I do with a 20 foot radiator?" Working >> out the details (the devil is indeed in the details!) sure is a lot >> easier with EZNEC than it is with physical modeling. > >Assuming a 20 ft. vertical with 20 ft. radials, how about >feeding it with an autotuner, like the SGC-230, and using >it for 40m-10m? It will also work at reduced power output >on 75m. John Ferrell W8CCW Article: 221127 of rec.radio.amateur.antenna From: "Frank" References: <1Qxxf.8331$dW3.1056@newssvr21.news.prodigy.com> <0NOxf.465$Jd.220@newssvr25.news.prodigy.net> Subject: Re: Brain Teaser Message-ID: <29Qxf.94004$6K2.41559@edtnps90> Date: Fri, 13 Jan 2006 16:01:02 GMT > Will Mathcad solve simultaneous equations? > -- > 73, Cecil http://www.qsl.net/w5dxp It can handle matrices. Frank Article: 221128 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Brain Teaser References: <1Qxxf.8331$dW3.1056@newssvr21.news.prodigy.com> <0NOxf.465$Jd.220@newssvr25.news.prodigy.net> <29Qxf.94004$6K2.41559@edtnps90> Message-ID: <4NQxf.494$Jd.25@newssvr25.news.prodigy.net> Date: Fri, 13 Jan 2006 16:43:44 GMT Frank wrote: >>Will Mathcad solve simultaneous equations? > > It can handle matrices. So how would you put these two equations in a matrix? 2*sin(B) = sin(A)/[2*sin(A)-1] 2*cos(B) = cos(A) :-) -- 73, Cecil, http://www.qsl.net/w5dxp Article: 221129 of rec.radio.amateur.antenna From: "amdx" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> Subject: Re: How to earn money with PAYPAL!!!! 37 Date: Thu, 19 Jan 2006 19:41:47 -0600 Message-ID: <14990$43d04031$18d6b488$14336@KNOLOGY.NET> Most young people, after paying social security taxes for a few years, and listening to the news, ARE familiar with a Ponzi scheme. (or scam) Mike wrote in message news:1137709653.497618.151660@o13g2000cwo.googlegroups.com... > Tom, realize that many newsgroup readers are so young that they are not > familiar with the Ponzi scam. Otherwise they would not buy programs > that perpetuate the scheme (or scam). > > http://home.nycap.rr.com/useless/ponzi/ > > Harry C. > Article: 221130 of rec.radio.amateur.antenna From: "amdx" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> Subject: Re: How to earn money with PAYPAL!!!! 37 Date: Thu, 19 Jan 2006 19:49:08 -0600 Message-ID: <174c$43d041ea$18d6b488$14817@KNOLOGY.NET> > Do I get a seniors discount? > GBrown You seniors! ya had 40 years to save yer money, an now you want the youngsters to pay more so you can get a discount. hurumph Mike Article: 221131 of rec.radio.amateur.antenna From: "Bill Turner" Subject: Re: HF-Ground Date: 20 Jan 2006 02:08:57 GMT Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Owen Duffy wrote: > Bill, I often see the assertion that it is better to not bury radials. > > Can you point me to any reputable texts or experimental evidence that > shows the difference between shallow buried radials and radials lying > "on top of the ground"? > > Corrosion is often cited as a reason to use insulated buried radials, > but is corrosion a significant risk in most locations. We widely use > buried copper water pipes here, and copper clad earthing electrodes > for the MEN power supply earthing, yet they don't seem to suffer > significant corrosion in most places. > > It seems to me that insulated buried radials are likely to be less > effective in a lightning protection role. > > Owen ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Your mind is already made up. Do as you like. Bill, W6WRT Article: 221132 of rec.radio.amateur.antenna From: "Crazy George" References: <1137691091.471022.293300@z14g2000cwz.googlegroups.com> Subject: Re: looking for antenna recommendation Date: Thu, 19 Jan 2006 20:46:37 -0600 Message-ID: <43d04f29@kcnews01> You can use that antenna, and don't need the triplexer. I would suggest looking for an appropriate fixed mount, something which will clamp to the rear rack for the bike, and use the mag base for other vehicles with larger area for a magnet to stick to. The antenna merely unscrews from the mount, so moving (or stealing) it is simple. -- Crazy George W5VPQ My real address is my ham call ARRL.NET The ATTGlobal is a SPAM trap. wrote in message news:1137691091.471022.293300@z14g2000cwz.googlegroups.com... > I'm looking for a recommendation for an external antenna to use with my > > Yaesu VX-7R handheld. > > This antenna would spend most of its life on a bicycle (on a rear rack > behind the seat), which is how I commute to/from work. However, I'd > like to be able to use it occasionally on a car/truck so I'm thinking a > > magnetic base would be the most flexible. > > Ideally it would cover all of the VX-7R's bands, or at least the > 6M/2M/70CM bands and it would have a cable with an SMA connector at the > > end. > > Ideally it would be something like Diamond's CR627B antenna > (http://www.rfparts.com/diamond/cr627b.html) but without needing a > triplexor and with a magnet mount. > > Now I realize that such a thing might not exist which is why I'm open > to suggestions that I drop the 6M band requirement which would lose me > the grounding requirement which would lose me the restriction against > magnet mount. > > Ideas? > > greg > Article: 221133 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: HF-Ground Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Date: Fri, 20 Jan 2006 02:51:18 GMT On 20 Jan 2006 02:08:57 GMT, "Bill Turner" wrote: >Owen Duffy wrote: > >> Bill, I often see the assertion that it is better to not bury radials. >> >> Can you point me to any reputable texts or experimental evidence that >> shows the difference between shallow buried radials and radials lying >> "on top of the ground"? >> >> Corrosion is often cited as a reason to use insulated buried radials, >> but is corrosion a significant risk in most locations. We widely use >> buried copper water pipes here, and copper clad earthing electrodes >> for the MEN power supply earthing, yet they don't seem to suffer >> significant corrosion in most places. >> >> It seems to me that insulated buried radials are likely to be less >> effective in a lightning protection role. >> >> Owen >~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > >Your mind is already made up. Do as you like. I note that you decline to subtantiate the reasons underlying your advice. Has anyone references to sound evidence that supports Bill's advice that radials "Lying on top of the ground is better." than buried. Owen -- Article: 221134 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: How to earn money with PAYPAL!!!! 37 References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> <174c$43d041ea$18d6b488$14817@KNOLOGY.NET> Message-ID: Date: Fri, 20 Jan 2006 03:06:24 GMT amdx wrote: > You seniors! ya had 40 years to save yer money, an now > you want the youngsters to pay more so you can get a discount. I won't live long enough to get back all I paid into social security plus interest. -- 73, Cecil http://www.qsl.net/w5dxp Article: 221135 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: HF-Ground Date: Thu, 19 Jan 2006 21:22:25 -0600 Message-ID: <11t0ltpe78fkj5e@corp.supernews.com> References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Owen Duffy wrote: > On 20 Jan 2006 02:08:57 GMT, "Bill Turner" wrote: > > >>Owen Duffy wrote: >> >> >>>Bill, I often see the assertion that it is better to not bury radials. >>> >>>Can you point me to any reputable texts or experimental evidence that >>>shows the difference between shallow buried radials and radials lying >>>"on top of the ground"? >>> >>>Corrosion is often cited as a reason to use insulated buried radials, >>>but is corrosion a significant risk in most locations. We widely use >>>buried copper water pipes here, and copper clad earthing electrodes >>>for the MEN power supply earthing, yet they don't seem to suffer >>>significant corrosion in most places. >>> >>>It seems to me that insulated buried radials are likely to be less >>>effective in a lightning protection role. >>> >>>Owen >> >>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >>Your mind is already made up. Do as you like. > > > I note that you decline to subtantiate the reasons underlying your > advice. > > Has anyone references to sound evidence that supports Bill's advice > that radials "Lying on top of the ground is better." than buried. > > Owen > -- Owen; Given the expertise that Bill has accumulated over the years and the good advise he has given to anyone who asks I think that your attitude needs modification. When you were in school did you challenge your teachers this way? I think not. If you diagreed you kept it to your self or checked it out on your own. For what it's worth everything that I have read tends towards placing the radials on the open ground, usually staked down so as to prevent tripping or getting caught in a lawn mower. Dave WD9BDZ Note to Bill: I know you don't need anyone to defend you but this guy isn't going to take any answer from anyone. I suggest that we drop him as a thread. I just know his response is going to be at me demanding positive confirmation. ;^).. Article: 221136 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: HF-Ground Message-ID: <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> Date: Fri, 20 Jan 2006 04:16:39 GMT On Thu, 19 Jan 2006 21:22:25 -0600, "David G. Nagel" wrote: >Owen; > >Given the expertise that Bill has accumulated over the years and the >good advise he has given to anyone who asks I think that your attitude >needs modification. When you were in school did you challenge your >teachers this way? I think not. If you diagreed you kept it to your self >or checked it out on your own. Dave, I don't agree, I have never had a teacher worth his salt who responded to polite questions as Bill did. No, I don't believe something just because I read it on the 'net, I would like to know why. >For what it's worth everything that I have read tends towards placing >the radials on the open ground, usually staked down so as to prevent >tripping or getting caught in a lawn mower. Yes, I see lots of web articles describing that in ham stations, but it is not the only approach that I see documented and talked about. In my limited experience, I have not seen commercial HF installations with radial / ground wires laid above ground in preference to being buried. The only cases I can recall were because of rock. Whilst there are articles around about the performance of shallow buried radials, I have not seen any that deal quantitatively with radials laid on the ground, or pinned to the ground as you describe, and the effects of those different installations on antenna efficiency. That is what I was asking about. Equally, there a plenty of articles where the author insists that radials cannot work near the ground and they need to be some distance above, some stating a quarter wave above. They can't all have "better" efficiency, the only way to know is to seek reasons why a configuration is better. Bill proposed a "better" configuration and declined to explain why / how it is better. Owen -- Article: 221137 of rec.radio.amateur.antenna From: "Charlie" Subject: Re: HF-Ground Date: Thu, 19 Jan 2006 23:31:32 -0600 Message-ID: <11t0te46fg2pd47@news.supernews.com> References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> I used about 1300 ft of insulated copper wire for my 72 radials. I chose to pin mine to the ground witrh fenc e staples. I did this work in the dead of winter. I then also covered them with a thin layer of soil. Come spring the grass grows and the radials are hidden and beneath the applied soil layer so as to not interfere with the lawn mower. Pictures of my installation for my Hustler 5BTV at this web page 1. http://www.ad5th.com/5-BTV.html -- Charlie-AD5TH www.deepsouthnet.net "Gary Schafer" wrote in message news:ehqvs15nfbeceg68lpkj26o47s4te3d1ad@4ax.com... > If you are also going to use the radials for a lightning protection > ground then bare wire is much better. > > 73 > Gary K4FMX > > > On 19 Jan 2006 06:04:29 -0800, john.minkjan@gmail.com wrote: > >>Question: >> >>Is you are making a HF-ground (radials just below the surface) Should >>these radials be insulated or not? >> >>73 John > Article: 221138 of rec.radio.amateur.antenna From: "Bill Turner" Subject: Re: HF-Ground Date: 20 Jan 2006 05:58:10 GMT Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> David G. Nagel wrote: > Dave WD9BDZ > > Note to Bill: I know you don't need anyone to defend you but this guy > isn't going to take any answer from anyone. I suggest that we drop > him as a thread. I just know his response is going to be at me > demanding positive confirmation. ;^).. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Thanks, Dave. He's history. (I wonder if he'd like positive confirmation?) 73, Bill W6WRT Article: 221139 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: HF-Ground Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> Date: Fri, 20 Jan 2006 06:56:42 GMT On Thu, 19 Jan 2006 22:19:04 -0800, Richard Clark wrote: >These three paragraphs reveal arguments that vary by application, >rather than by degree. It seems to me that most AM stations' ground >fields are shallow buried in gravel simply to permit foot traffic. The >HAARP site uses a grid that is elevated sufficiently to allow >vehicular traffic. Neither really attend lightning as they are more >ground screens and principally constructed for RF. Yes, I understand that a ground system may be called upon to perform a role as the other terminal of a Marconi for instance, and as the drain for lightning or other EMP. Hence my earlier comment that a rule of thumb that buried radials should be insulated seems to deny fullest lightning protection to mitigate a small risk of corrosion. > >I found a much more compelling report in: >UNITED STATES DEPARTMENT OF AGRICULTURE >Rural Electrification Administration >REA BULLETIN 1751F-802 >SUBJECT: Electrical Protection Grounding Fundamentals >Which is vastly more comprehensive and directly answers these >questions when viewed in the terms of the resistivity of the earth >connection. OK, I found it and it is substantial. It will be an interesting read, thank you for the pointer. It appears to be focused more on power / lighting protection that an antenna ground system. For others, the URL is http://www.usda.gov/rus/telecom/publications/pdf_files/1751f802.pdf . One of the things that intrigues me is the common "expert" advice to cut radials for 7MHz to 33' long and bury them. It seems to me that when buried and considering the wire as a transmission line, the velocity factor will be somewhere between 0.3 and 0.8 depending on the soil type, so that 33' is likely to be closer to a half wave electrically, and present a relatively high and reactive impedance at the antenna base if it were not for the attenuation of the wave on the radial. It would seem a length more like 17' to 20' would be a better estimate by the SWAG method (Scientific Wild Arsed Guess), although if ground attenuation is high enough, it could be cut shorter and the extra wire used for another radial for a more effective solution. More when I digest some of the article. Thanks again... Owen -- Article: 221140 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: HF-Ground Date: Fri, 20 Jan 2006 01:48:00 -0800 Message-ID: <11t1ceh5gjs7i95@corp.supernews.com> References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Owen Duffy wrote: > > Bill, I often see the assertion that it is better to not bury radials. > > Can you point me to any reputable texts or experimental evidence that > shows the difference between shallow buried radials and radials lying > "on top of the ground"? > > Corrosion is often cited as a reason to use insulated buried radials, > but is corrosion a significant risk in most locations. We widely use > buried copper water pipes here, and copper clad earthing electrodes > for the MEN power supply earthing, yet they don't seem to suffer > significant corrosion in most places. > > It seems to me that insulated buried radials are likely to be less > effective in a lightning protection role. > > Owen You're asking some good questions. Many years ago, I was doing some ground system experiments with a vertical antenna. I had strung a bunch of radials, consisting of small insulated hookup wire, on the surface of the ground and I was measuring antenna input impedance. I was surprised to discover distinct resonance effects as the radial lengths were changed, something which I hadn't expected -- they were acting more like elevated than buried radials. It was summertime and the clay ground was pretty dry. Then I took some pieces of mild steel wire and "stapled" the wires down to conform with the ground and bring the wires into close contact with it. The resonant effects disappeared and the radials acted more like buried ones. I concluded that even a very small air gap between the radials and the ground provided some independence from the ground. More recently I've done some modeling to try and understand the phenomenon a bit better. I'll give those results in my response to another of your recent postings. Oh, as for corrosion -- I'm sure it depends on the soil. But there's no harm in using insulated wire, as far as RF ground effectiveness goes. I suppose it would limit the lighning protection voltage to the insulation voltage, however. Roy Lewallen, W7EL Article: 221141 of rec.radio.amateur.antenna From: "Dr.Ace" References: Subject: Re: Lightning Arrestor & Protection Of Receiver ? Date: Fri, 20 Jan 2006 04:58:48 -0500 Message-ID: <94765$43d0b434$4e0bd10$27948@DIALUPUSA.NET> "Robert11" wrote in message news:CdSdnW2_R4YMFlLenZ2dnUVZ_t-dnZ2d@comcast.com... > Hello: > > Very interesting comments on my question of a few days ago re lightning > arrestors. > Thank you all for trying to educate me on this subject; really find it > confusing. > Thread is a bit buried by now, so thought I'd start another one. > > I fully understand that the best approach is to (also) just disconnect > everything. > > But if not around, here's what I don't understand and concerns me. > > Assuming a "nearby" strike, and a subsequent emp pulse that's picked up by > a receive only antenna > wire strung outside: > > No matter how quickly an arrestor's gas tube fires, and diverts the pulse > to a good RF ground, the fact that it takes > a few hundred volt threshold to fire makes "any" gas tube type of arrestor > almost worthless re the protection of a receiver whose front end certainly > won't take a few hundred volts, even for u-seconds, probably. > > Do you agree with this statement, or am I missing something ? > > Thanks, > Bob > Hi Bob, I'm Ace - WH2T. Here's my story. So far I have been very lucky. Neighbors closest on my north and south sides have both been hit, BAD SEVERE strikes. We live on a hill. I had a strike take out a cheap portable TV that was in the kitchen and it blew a fuse in a VCR. It also came in the telephone line and blew up some FM intercoms that were connected to the telephone line. After that happened I had a commercial lightning arrestor installed by my electric power company at the electric meter. I use 2 HF antennas, a 272 ft delta loop and a 160 meter band 1/4 wave inverted L antenna, both antennas go thru my MFJ-989C Tuner . When I am not on the air I leave the antenna switch on the tuner in the "Dummy Load" position. That connects a 300 watt 50 ohm resistor to the radio's antenna jack and grounds both antennas. The main lightning problems I have had in the 12 years at this QTH are surges coming in the telephone line. I noticed when I moved here that all the telephone jacks in the house were black. I lost 9 computer modems in short order. I installed the smallest fast blow fuses I could find in both sides of the telephone line (they are under 100 ma) . The next time there was a nearby strike it blew both fuses and still blew my computer modem. After that I installed three 130 Volt MOVs outside the house in the telephone box , one across the telephone line and one from each side of the telephone line to ground. I also installed a very small pigtail neon lamp between or across the 2 sides of the telephone line. It acts as a gas tube type of arrestor, and lights when the telephone rings, or when lightning strikes nearby; the threshold to fire is under 100 volts. I also installed a DPDT knife switch , to break the telephone line when the computer is not connected to the internet. No further problems. I live out in the country dial up is all that is available here other than expensive satellite access. Anyway , now on to your question. I got the following Info from another ham. >From my commercial broadcast days the lightning control solution for tall insulated base AM towers (which were always experiencing direct lightning strikes) was to use 2 inch diameter copper balls spaced 1/4 to 1/2 inch from each other (depending on peak RF voltage present) at the base of each tower on heavy arms as a lightning spark gap. Then the 1/4 inch tubing feeding station RF into each tower base would be formed into a 3 turn loop with a 12 inch diameter, with about 2 inch spacing between each turn. I would do the same with the coax feeding repeaters and studio-transmitter links on these towers. I never lost any equipment using these techniques. I realized I have to mention that I use an inductive RF coupling- impedance transformer in my homemade transmatch in order to eliminate a direct dc path from the ladder line to the transceiver input. I also use high tension teflon coated wire for the primary turns in the transformer. Lightning would be common mode on the transmission line and therefore not inductively coupled through the transmatch. The issue then becomes voltage breakdown between transformer primary and secondary windings (along with minor capacitive coupling), hence the teflon coated wire. Concerning possible lightning on the ladder line, I use adjustable spark gaps from each conductor to ground outside of my building. I hope this is of some help. Ace - www.WH2T.com Article: 221142 of rec.radio.amateur.antenna From: "Dr.Ace" References: <1137539656.712611.283320@g47g2000cwa.googlegroups.com> Subject: Re: Larger size HF antenna's Date: Fri, 20 Jan 2006 05:06:26 -0500 Message-ID: "Maarten" wrote in message news:1137539656.712611.283320@g47g2000cwa.googlegroups.com... > Hi, > > I seek some help, advise or suggestions on HF antenna's. I've bought a > house with a plot of approx 330 x 80 ft / 100 x 23 mtr available for HF > antenna's. > But when I research HAM HF antenna's, home build or commercially > available, I only find a lot of small, smaller and smallest HF > antenna's (eg. wire antenna's, inverted V, T2DF) that don't take full > advantage of the size of my land available. On the other end of the > spectrum there are plans for very, VERY large antenna's like Rhombic > and Beverage. For this size of antenna's my plot is to small. > > Do you have suggestions for HF antenna's I should check out? Let me > know in this forum or pm me. Thanx in advance. 73 > > Maarten > maartenkoning2002 (at) yahoo.com > Check out - http://www.bloomington.in.us/~wh2t/ant.htm I discuss some large antennas. 73, Ace - WH2T Article: 221143 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: HF-Ground Date: Fri, 20 Jan 2006 02:07:20 -0800 Message-ID: <11t1dipb6b2jvde@corp.supernews.com> References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> Owen Duffy wrote: > . . . > One of the things that intrigues me is the common "expert" advice to > cut radials for 7MHz to 33' long and bury them. It seems to me that > when buried and considering the wire as a transmission line, the > velocity factor will be somewhere between 0.3 and 0.8 depending on the > soil type, so that 33' is likely to be closer to a half wave > electrically, and present a relatively high and reactive impedance at > the antenna base if it were not for the attenuation of the wave on the > radial. It would seem a length more like 17' to 20' would be a better > estimate by the SWAG method (Scientific Wild Arsed Guess), although if > ground attenuation is high enough, it could be cut shorter and the > extra wire used for another radial for a more effective solution. Modeling clearly shows that using elevated radials which are too long degrades the efficiency. A quarter wavelength can be determined by constructing a dipole at the height of the proposed radial system and adjusting it to resonance. The maximum length of the radials is half the length of that dipole. If you make them longer, efficiency drops. Very close to the ground, the length of a quarter wavelength decreases substantially, so a free-space quarter wavelength can easily be too long. Modeling presents a very idealized situation, overly so when dealing with ground. But I believe the general trends and conclusions are instructive. I modeled a 40 meter vertical over average ground. It had four 34 foot radials, which were quarter wave resonant when elevated very high. As I lowered the radials from one foot high to 0.1 inch high, the gain dropped 4 dB. The main cause of the drop was that the radials were becoming too long at the low height above ground. Shortening them to 19.6 feet, the resonant length at that height, increased the field strength by 2.45 dB. Burying them lowered the field strength to 1.7 dB below the field strength when 0.1 inch above the ground and of proper length. There wasn't any substantial change in field strength as the length was increased beyond about 30 feet, or when the depth was varied >from 0.1 to 6 inches. These changes in field strength are solely due to changes in efficiency; the pattern shape stays the same. When modeled at 0.1 inch above the ground, the radial current distribution is approximately sinusoidal, as in elevated radials. When buried, even an inch, the current decays in an approximately exponential fashion away from the center. In the case of the modeled antenna system, the current was substantially zero beyond about 40 feet. Conclusions are: 1. A small number of radials just above the ground are theoretically a bit more efficient than the same number of buried radials, providing that they're not longer than a resonant quarter wavelength at that height. I say theoretically, though, because I believe it would be impossible to maintain current balance in the radials at a low height. So one or two radials would likely hog all the current, resulting in a less efficient system. 2. Making elevated radials too long, even if the elevation consists of being just above the ground, can seriously reduce the antenna efficiency. Buried radials, on the other hand, are insensitive to length provided they're sufficiently long. This latter fact is well known. I've found in other modeling I've done that making elevated radials shorter than a resonant quarter wavelength doesn't negatively impact the efficiency. So if you have to guess, guess on the short side. The amount of differences you'll see in real antenna systems will vary quite a bit depending on ground characteristics, frequency, and number of radials. And it would be impossible to suspend radials precisely over a perfectly flat and homogeneous ground as I've done with the models. But I believe the conclusions are valid. Roy Lewallen, W7EL Article: 221144 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: HF-Ground References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> Message-ID: Date: Fri, 20 Jan 2006 12:07:36 GMT Owen Duffy wrote: > Whilst there are articles around about the performance of shallow > buried radials, I have not seen any that deal quantitatively with > radials laid on the ground, or pinned to the ground as you describe, > and the effects of those different installations on antenna > efficiency. Will NEC-4 accurately model radials at different depths? -- 73, Cecil http://www.qsl.net/w5dxp Article: 221145 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: HF-Ground References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> Message-ID: <%W4Af.15171$Yu.2670@newssvr27.news.prodigy.net> Date: Fri, 20 Jan 2006 12:44:43 GMT Owen Duffy wrote: > One of the things that intrigues me is the common "expert" advice to > cut radials for 7MHz to 33' long and bury them. It seems to me that > when buried and considering the wire as a transmission line, the > velocity factor will be somewhere between 0.3 and 0.8 depending on the > soil type, so that 33' is likely to be closer to a half wave > electrically, and present a relatively high and reactive impedance at > the antenna base if it were not for the attenuation of the wave on the > radial. You seem to be referring to the feedpoint impedance of a single radial the virtual impedance of which would depend upon the magnitude and phase of the forward and reflected wave on the radial wire. The single-wire transmission line formula gives a Z0 for each radial as less than 100 ohms. Given the probability of a high degree of attenuation and the number of radials in parallel, the impedance presented at the base is likely to be relatively low no matter what the length of the radials assuming an electrical length of longer than 1/4WL. -- 73, Cecil http://www.qsl.net/w5dxp Article: 221146 of rec.radio.amateur.antenna From: Bob Miller Subject: Re: HF-Ground Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0te46fg2pd47@news.supernews.com> Date: Fri, 20 Jan 2006 12:50:35 GMT On Thu, 19 Jan 2006 23:31:32 -0600, "Charlie" wrote: >I used about 1300 ft of insulated copper wire for my 72 radials. So they're about 18 feet long, giving you a short, dense pattern? bob k5qwg > I chose to >pin mine to the ground witrh fenc e staples. I did this work in the dead of >winter. I then also covered them with a thin layer of soil. Come spring the >grass grows and the radials are hidden and beneath the applied soil layer so >as to not interfere with the lawn mower. > >Pictures of my installation for my Hustler 5BTV at this web page > >1. http://www.ad5th.com/5-BTV.html Article: 221147 of rec.radio.amateur.antenna From: "Richard Fry" References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> <11t1dipb6b2jvde@corp.supernews.com> Subject: Re: HF-Ground Date: Fri, 20 Jan 2006 07:20:06 -0600 Message-ID: <43d0e2c9_5@newsfeed.slurp.net> "Roy Lewallen" wrote > 2. Making elevated radials too long, even if the elevation consists of > being just above the ground, can seriously reduce the antenna efficiency. > Buried radials, on the other hand, are insensitive to length provided > they're sufficiently long. This latter fact is well known. I've found in > other modeling I've done that making elevated radials shorter than a > resonant quarter wavelength doesn't negatively impact the efficiency. So > if you have to guess, guess on the short side. _____________ NEC studies of a 1/4-wave vertical radiator working against three 1/4-wave horizontal radials at 120 degrees, when all elements are elevated 12 feet above a perfect ground plane show virtually identical peak gain as when the same radiator minus the radials is mounted with its base at the perfect ground plane, and connects to it though two ohms (about the same ground loss as produced by 120 buried radials, each 1/4-wave long). As few as four elevated radials have been used at AM broadcast sites where a typical system of 120 buried radials was impossible due to rocky terrain. The FCC "efficiency" of these radiator systems meets/exceed FCC requirements for radiation at 1 km. Conclusion: a few elevated radials can be the electrical equivalent of a classic "Brown, Lewis & Epstein" system of 113 (or 120)buried radials. RF Article: 221148 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Re: HF-Ground Date: Fri, 20 Jan 2006 13:56:28 +0000 (UTC) Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> "Owen Duffy" wrote > Whilst there are articles around about the performance of shallow > buried radials, I have not seen any that deal quantitatively with > radials laid on the ground, or pinned to the ground as you describe, > and the effects of those different installations on antenna > efficiency. ======================================== Owen, you may be interested in Program RADIALS3. Once radials are buried in the ground, just below soil surface, I don't think depth of burial matters very much. But things happen very fast when resting on the soil surface and conductor height is raised only slightly. Consider a single counterpoise wire. When resting on the soil surface propagation velocity along the wire is about half of the free space velocity. Propagation velocity increases fast as height increases. When height is greater than length the VF is very nearly 1. When resting on the ground there is an equivalent loss resistance distributed along the wire due to the mutual impedance with the ground. The input resistance at resonance is high. Q is very small. But a lot depends on soil resistivity. With increasing height the coupling with ground decreases and so does the input resistance. When height is greater than length the input resistance is due only to conductor loss resistance and resonant Q is high. Resonant frequency increases with height due to the increase in VF. The increase in VF is due to decrease in capacitance to ground when considered as a transmission line. Changes in capacitance, VF, resonant frequency, and induced loss in the ground, mostly occur in first few inches of height above ground but cannot be neglected until height is roughly greater than length. ---- ........................................................... Regards from Reg, G4FGQ For Free Radio Design Software go to http://www.btinternet.com/~g4fgq.regp ........................................................... Article: 221149 of rec.radio.amateur.antenna From: "Richard Fry" References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> <11t1dipb6b2jvde@corp.supernews.com> <43d0e2c9_5@newsfeed.slurp.net> Subject: Re: HF-Ground Date: Fri, 20 Jan 2006 08:09:59 -0600 Message-ID: <43d0ee79_3@newsfeed.slurp.net> "Richard Fry" > NEC studies of a 1/4-wave vertical radiator working against three 1/4-wave > horizontal radials at 120 degrees, when all elements are elevated 12 feet > above a perfect ground plane... etc ____________ I neglected to include that the frequency in these studies was 1 MHz, so elevation of the system was about 0.012 wavelengths (Reg). RF Article: 221150 of rec.radio.amateur.antenna From: "Charles Brabham" Subject: HamPoll.Com wants your opinions Message-ID: Date: Fri, 20 Jan 2006 15:31:38 GMT HamPoll exists in order to give amateurs a chance to speak for themselves and to provide accurate, reliable polling data on a variety of issues related to the amateur radio service. You are welcome to browse the polling data we have, but we especially encourage US amateurs visiting here to register with thier callsign and vote in the HamPoll Polling Station. Whether you come to browse, to discuss or submit new polls, or to tender your vote, be sure to visit regularly as new polls are included from time to time and the poll data changes as more hams participate day to day. Stop by at: http://www.hampoll.com Charles Brabham, N5PVL HamPoll Administrator Article: 221151 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Larger size HF antenna's Date: Fri, 20 Jan 2006 09:44:52 -0600 Message-ID: <12633-43D10574-1718@storefull-3254.bay.webtv.net> References: Congratulations Dr. Ace! You sure know how to trash a place! Best regards, Richard Harrison, KB5WZI Article: 221152 of rec.radio.amateur.antenna From: N7ZZT - Eric Oyen Subject: Re: noise bridge References: <678ea$43ccf378$42a1bfc2$9536@FUSE.NET> Message-ID: <7S7Af.171$2o5.140@dukeread11> Date: Fri, 20 Jan 2006 09:04:10 -0700 jawod wrote: > As I read through the various opinions regarding antenna load, > impedance, etc., most of the arguments seem to be mathematically oriented. > > Does anyone use a noise bridge (as mentioned in ARRL pubs) to determine > the feedpoint impedance? I use one rather often as a means of tuning my antenna for best reception on HF (not transmit). I have had a general or 2 test my assumption and they seem to hold up (with some minor tweaking to clean up stray impedances). > > Is there a source for these bridges? mfj makes a nice antenna noise bridge. its simple to use too (only 1 knob - power).This device is used concurrently with a tuner for best results. -- DE N7ZZT Eric Oyen Phoenix, Arizona e-mail: n7zzt(at)hotmail(dot)com the difference between intelligence and stupidity is that intelligence has its limits. Article: 221153 of rec.radio.amateur.antenna From: Bob Bob Subject: Re: what are Microwave Antennas? References: <1137700291.373977.273720@g44g2000cwa.googlegroups.com> Message-ID: Date: Fri, 20 Jan 2006 09:59:26 -0600 Hmmm Well I can see that the term doesnt have a rigid definition as such. The antenna part is obvious and I hope doesnt need me to elaborate. The word microwave generally means a "small wavelength", probably anything higher than the frequency of 1Ghz but it may be defined more accurately elsewehere. The wavelength is inversely proportional to the frequency and at 1GHz is about 300mm. Microwave communciation is generally characterised by short distances and line of sight or visible paths between one end and the other. Examples might be mobile phones (900MHz, 1.8GHz, 2.4GHz), WiFi computer links (2.4GHz, 5.6GHz), high capacity data links (2-25GHz) and so on. (1000MHz=1GHz) Once the path becomes obstructed or goes over the horizon the signal gets severely attenuated. Antennas are designed and manufactured for the service and range required. - Something to control a toy truck with you'll want to radiate in as wide as a coverage angle as possible. When you tilt the controller back and forth you still want it to work. Keep in mind that microwave radiation also reflects of objects pretty well, so for short range this is often the mode of operation. - A WiFi antenna on a laptop and a users mobile phone generally needs to radiate in a roughly horizontal direction but at every azimath. By concentrating the radiation in a desired direction you get better range or can get away with using less power. The WiFI and mobile phone base station on tbe other hand may have more stringent radiation and directionality requirements. The service area may be deliberately restricted by the choice of antennas - A high capacity microwave data link will pretty well always use high gain high directive antennas at each end. This is so you can make the signal work (say) upto 50km with low power. It is also very important for these links to only have a direct (non reflective) path between each other. The extra time delay introduced by a reflection can foul up the link operation. (You may have heard the term "multipathing") Generally speaking an antenna is made up of half wavelength elements at the desired frequency, arranged to concentrate the radiation in the desired direction. (look up the antenna terms 'colinear' and 'yagi') More in common use are antennas that use large reflectors behind the element connected to the cable. (look up 'parabolic dish', 'gridpack' & 'patch antennas'. What you see on a comms tower is the same theory of operation as a deep space tracking dish. The theory of operation of a microwave antenna is pretty much the same as an antenna made for a lower frequency, just everything is much smaller! From here on in you'll have to do some research on what antenna gain is and how to build it into the structure. Cheers Bob VK2YQA Bug3 wrote: > > Wondering what are microwave antennas, what do they do, how do they > work, etc? Article: 221154 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Lightning Arrestor & Protection Of Receiver ? Date: Fri, 20 Jan 2006 12:15:14 -0600 Message-ID: <19272-43D128B2-1581@storefull-3255.bay.webtv.net> References: <94765$43d0b434$4e0bd10$27948@DIALUPUSA.NET> Ace, WH2T wrote: "I realized I have to mention that I use an inductive RF coupling - impedance transformer in my homemade transmatch in order to eliminate a direct d-c path from the ladder line to the transceiver input." Lightning is a threat to antennas and to items connected with them. Static charges may build in a time of clear skies, especially ahead of a thunderstorm. Guy-wire insulators often flashover to announce a storm is approaching. Radio towers in broadcast stations get lightning strikes over and over again, but loss of equipment or even air time is minimal. The beacon atop a tower is most exposed, but it is protected by a vertical metal rod attached to the tower near the beacon and extending well above it. Often this rod is an 8-ft Copperweld groundrod bolted to the tower with its tip point skyward. Pits on the rod show it takes hits. Beacon survival shows it does not take hits. The protection works. Guy-wire insulators are often doubled or tripled at the tower attachment points to discourage flashovers here. An air gap is provided across the tower base insulator. In theory, lightning ionizes rhe air in the gap and shunts the charge to ground before it gets into the feeder system. Spacing is usually adjusted to only slightly wider than the gap will breakdown on the transmitted signal. I`ve examined many of these ball gaps and horn gaps and seen no evidence of flashover. To discourage lightning, a turn or two is often made in the conductor feeding the tower. I haven`t seen pts on the balls or horn gaps indicating that the tiny inductance added by a turn or two in the feedwire does any good. A static-drain choke which has a very high impedance at the operating frequency, but has a low d-c resistance, is often connected across the tower`s base insulator on the line side of the base impedance matching unit. It may be placed on the tower side of the matching unit if there is no d-c continuity through the matching unit. All the stations I`ve worked in had an air-core 1:1 coupling transformer in the tower matching unit. Primary and secondary share the same axis but are seoarated by a metal rake which serves as a Faraday screen. It is a picket fence between the coils. The tines of the rake have no electrical connection at one end, but the backside of the rake connects all the tines together and firmly grounds them. The rake allows magnetic coupling between the coils but prohibits electric field coupling between the coils. The rake is a very effective lightning stopper. It is full of pits where lightning has struck. Best regards, Richard Harrison, KB5WZI Article: 221155 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Re: Lightning Arrestor & Protection Of Receiver ? Date: Fri, 20 Jan 2006 19:34:23 +0000 (UTC) Message-ID: References: When lightning directly strikes either the antenna or the dwelling, despite all the precautions, ANYTHING can happen. The direct strike is just as likely to be on the dwelling and its occupants as the ordinary radio antenna. So concentrate precautions on your house, the more valuable of your possessions. Only then think about your inverted-L and your radio equipment. Just a logical way of thinking about things. A direct strike will probably never happen anyway. ========================================= Article: 221156 of rec.radio.amateur.antenna From: "amdx" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> <14990$43d04031$18d6b488$14336@KNOLOGY.NET> <1137784735.650874.68910@o13g2000cwo.googlegroups.com> Subject: Re: How to earn money with PAYPAL!!!! 37 Date: Fri, 20 Jan 2006 13:58:59 -0600 Message-ID: >still there are enough of the young guys and girls that are > ignorant of the Ponzi type scam > > Curmudgeonly yours, Harry C. > A class on consumerism ("they want to take your money") should be a required class in middle school. And don't get me started on all the bogus, weight loss products, grow tall products, second grade teacher developed common cold product, herbs that will stop diabetes and heart disease, anti hairloss products, improve your memory, shrink your prostate, grow penis, cleanse your blood, detoxify your liver, give you more energy, stop your joint pain, make you more appealing to the opposite sex, , improve your eyesight, slow the ageing process, improve your circulation, make exercise easy, prevent cancer, make your skin beautiful, health restoring magnetic shoe inserts, magnetic water enhancers. I think you got me started ;-0 And speaking of curmudgeons, Andy Rooney said " Happy birthday?--I DON'T THINK SO." Mike, I promise to enjoy my day! Bye Article: 221157 of rec.radio.amateur.antenna From: Owen Duffy Subject: Re: HF-Ground Message-ID: <3mi2t15vgba1h1ctc421tk6olunkuigtvk@4ax.com> References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> Date: Fri, 20 Jan 2006 20:43:15 GMT On Fri, 20 Jan 2006 13:56:28 +0000 (UTC), "Reg Edwards" wrote: >Owen, you may be interested in Program RADIALS3. >For Free Radio Design Software go to >http://www.btinternet.com/~g4fgq.regp Reg, did I miss something. RADIALS3 doesn't seem to be in the index at http://www.btinternet.com/~g4fgq.regp/page3.html#S301%22 Owen -- Article: 221158 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Lightning Arrestor & Protection Of Receiver ? Date: Fri, 20 Jan 2006 14:51:20 -0600 Message-ID: <20330-43D14D48-1860@storefull-3251.bay.webtv.net> References: Reg, G4FGQ wrote: "The direct strike is just as likely to be on the dwelling and its occcupants as the ordinary radio antennas." True, unless the antennas are much taller than the dwelling. That was the case of the radio stations. Occupants were safe, protected by the tall radio towers. Just as the towertop rod protects the beacon. the tower protects the nearby structures under it (within its "cone of protection"). Agreed that people are more important than radios. I don`t want to cede people or radios. Here on the Gulfcoast of the U.S.A., the climate is semitropical and thunderstorms are abundant. Radio towers are struck by lightning repeatedly by nearly every passing thunderstorm and these are frequent. Where I`ve worked, buildings on the station`s property were never struck, nor was a serious electric surge ever transmitted into any building other than one of the "dog houses" at the towers where it is expected.and prepared for the stroke. The buildings on radio station properties are protected by big lightning rods, the towers, just as Benjamin Franklin predicted in 1735. Best regards, Richard Harrison, KB5WZI Article: 221159 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: HF-Ground References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Message-ID: Date: Fri, 20 Jan 2006 21:05:51 GMT Owen Duffy wrote: > I often see the assertion that it is better to not bury radials. Here's a data point for all. I'm taking down my 102 ft dipole and putting back up my 130 ft dipole. I measured the resonant frequency and feedpoint impedance of the 102 ft dipole both while hanging in the air as a V and laying on the ground. Hanging in the air: Resonant at 4.52 MHz with a feedpoint impedance of 22 ohms. Laying on the ground: Resonant at 2.17 MHz with a feedpoint impedance of 108 ohms. Laying the insulated wires on the ground resulted in a reduction of VF of about 50%. The marked increase in feedpoint impedance was due to the attenuation of the reflected waves arriving back at the feedpoint and agrees closely with my calculations of such. -- 73, Cecil http://www.qsl.net/w5dxp Article: 221160 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: HF-Ground References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Message-ID: Date: Fri, 20 Jan 2006 21:10:06 GMT Cecil Moore wrote: > Laying the insulated wires on the ground resulted in a > reduction of VF of about 50%. The marked increase in > feedpoint impedance was due to the attenuation of the > reflected waves arriving back at the feedpoint and > agrees closely with my calculations of such. I forgot to say: Note that the dipole laying on the ground was close to one wavelength, yet the feedpoint impedance is not all that high. It would appear that 1/2 wavelength buried radials do NOT present a high impedance. -- 73, Cecil http://www.qsl.net/w5dxp Article: 221161 of rec.radio.amateur.antenna Message-ID: <43D181DC.19682475@worldnet.att.net> From: "John O. Kopf" Subject: Re: How to earn money with PAYPAL!!!! 37 References: Date: Sat, 21 Jan 2006 00:35:02 GMT Just forward all of the pyramid scam messages to: FEDERAL TRADE COMISSION PYRAMID SCAM PROSECUTION A copy to the sender saying that posting this is a FEDERAL OFFENSE helps as well! :>} JK hhc314@yahoo.com wrote: > > amdx, still there are enough of the young guys and girls that are > ignorant of the Ponzi type scam and buy these worthless software > packages that annoy us all on a daily basis. SNIP Article: 221162 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Re: HF-Ground Date: Sat, 21 Jan 2006 00:55:13 +0000 (UTC) Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> <11t0ltpe78fkj5e@corp.supernews.com> <0an0t15bj93jvgh510cfcbe1ikadplvk8p@4ax.com> <3mi2t15vgba1h1ctc421tk6olunkuigtvk@4ax.com> "Owen Duffy" wrote > > >For Free Radio Design Software go to > >http://www.btinternet.com/~g4fgq.regp > > Reg, did I miss something. RADIALS3 doesn't seem to be in the index at > http://www.btinternet.com/~g4fgq.regp/page3.html#S301%22 > > Owen ---------------------------------------------------------------------- ---- Very sorry Owen. My mistake. The name of the program is RADIALS2. It deals only with buried radials. I am at present trying to write a program about coil-loaded counterpoises and artificial grounds at low heights. But it's a beast to model mathematically. ---- Reg. Article: 221163 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Re: HF-Ground Date: Sat, 21 Jan 2006 03:38:08 +0000 (UTC) Message-ID: References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> "Cecil Moore" wrote It would appear that 1/2 wavelength > buried radials do NOT present a high impedance. > =============================== Cec, . . . . as demonstrated by program RADIALS2 which treats radials as transmission lines. As they truly are. The permittivity of soil surrounding buried radials is high. It is due to the moisture content of the soil. Water has a high permittivity K = about 80. If the moisture content is 20 percent then the permittivity is roughly K = 16 plus a little bit for the dry content. The poor, low conductance of the dielectric material, in conjunction with wire inductance, also has an effect. The soil is mainly, minute rock particles and a little air. Rock has K = 4 or 5. Air = 1. Velocity factor of any transmission line = 1 / Sqrt( Permittivity ). In some circumstances, there may be no point in having radial lengths longer than 1/10th or 1/12th of the free-space wavelength. If the soil has any magnetic material in it then the velocity is even lower. But it's a waste of time trying to tune buried radials by sprinkling iron filings around your garden. The attenuation along buried radials is usually so high that even 1/4-wave resonance doesn't show up. Impedance versus length at low HF is a smooth curve approximately equal to Zo. But input impedance of a set of radials is NOT equal to the impedance of the individual wires all in parallel. They interact with each other. The Law of Diminishing Returns applies. In perfectly dry desert sand with a resistivity of 5,000 or 10,000 ohm-metres and K = 3, the 1/2-wave resonance may appear on an impedance vs frequency curve. Program RADIALS2 shows this effect as evidence of reasonable modelling accuracy. This is a case of ground loss decreasing as soil resistivity increases further. It appears attenuation is a maximum when soil resistivity is around several hundred ohm-metres (377?). Which is quite a poor soil. (I once had a garden of sandy soil. Resistivity was 400 ohm-metres even in wet weather. Eventually I moved house. SR fell to 70. On the 160m band 7 radials, each about 10 feet long, plus the cold water pipe, were good enough with a 3/8 wave inverted -L. I never tried B,L,E's 118 radials, 1 wavelength long.) But in bone dry sand-desert soil, just rock mixed with air, at low HF one would not use a system of radials under a 1/4-wave vertical. The antenna could be a horizontal dipole lying on the ground. ;o) ---- ........................................................... Regards from Reg, G4FGQ For Free Radio Design Software go to http://www.btinternet.com/~g4fgq.regp ........................................................... Article: 221164 of rec.radio.amateur.antenna From: "Tom the Canuck" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> <174c$43d041ea$18d6b488$14817@KNOLOGY.NET> <1137785765.969348.81760@g14g2000cwa.googlegroups.com> Subject: Re: How to earn money with PAYPAL!!!! 37 Message-ID: Date: Sat, 21 Jan 2006 00:27:41 -0500 "GBrown" wrote in message news:Q42dnVY9e9WoJkzeRVn-ug@gwi.net... > And, how do you know that they didn't pay into the system. Was it the color > of there skin, there facial features, or did you have an inside scoop? What > makes you think there not citizens? Part of the problem is jumping to > conclusions. > I do understand your point and it does happen but to just blurt out > statements that mite be false, well............... > > -- > > wrote in message > news:1137785765.969348.81760@g14g2000cwa.googlegroups.com... > > Same here Cecil. > > > > The young kids don't have a clue about Social Security, because it > > isn't important to them at their time in life, nor was it for me when I > > was 25. None of us ever thought that we would live to see 65, hence it > > was just like income tax, something that you simply had to pay. Wow there GBrown, Don't blast Harry C. He has a point. Up here in the great white north known as Canada, I have seen deadbeats claim Social Insurance. They do nothing to contribte to society, they just wait for 'check day' to pay the rent, and blow the rest on beer and drugs only to be broke in a day or two until the next month*. My taxes go towards paying them. Is that right? I think not. Is it the same in the states? If one day I need to do the same, rest assured it will NOT be wasted on beer and drugs. I have paid into this for many years. I would just want something back from all the $$$ I had deducted from my pay should I ever need it. Tom the Canuck. * Do they eat food? Utilities? I do not know and do not want to.. What they do for the rest of the month is beyond me. Article: 221165 of rec.radio.amateur.antenna From: "Tom the Canuck" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> <14990$43d04031$18d6b488$14336@KNOLOGY.NET> <1137784735.650874.68910@o13g2000cwo.googlegroups.com> <43D181DC.19682475@worldnet.att.net> Subject: Re: How to earn money with PAYPAL!!!! 37 Message-ID: Date: Sat, 21 Jan 2006 00:45:58 -0500 "John O. Kopf" wrote in message news:43D181DC.19682475@worldnet.att.net... > Just forward all of the pyramid scam messages to: > FEDERAL TRADE COMISSION PYRAMID SCAM PROSECUTION > > A copy to the sender saying that posting this is a FEDERAL OFFENSE helps > as well! :>} > > JK > > Hey John, I like your post. Good idea. What about those telemarketing companies that sell worthless products from Canada to the US? There is a telemarketing company in the building where I worked. Being a smoker, I got to know a few of the frequently replaced telemarketing sales staff. The company in question sells a 'directory' of businesses in the states. While smoking, I asked one of the sales people what the product they were selling was good for. The reply was toilet paper. I would tend to agree. I believe there were several complaints to the attorney general of a particular state(s) and I had a smile on my face when the local police raided their place of business. Too bad they were back up and running the very next week. How can we stop these assholes? It puts a bad name on Canada. I feel ashamed that they can operate freely here. Tom the Canuck. Article: 221166 of rec.radio.amateur.antenna From: "Dr.Ace" References: <12633-43D10574-1718@storefull-3254.bay.webtv.net> Subject: Re: Larger size HF antenna's Date: Sat, 21 Jan 2006 01:09:18 -0500 Message-ID: <1816$43d1d00b$4fc61f3$6762@DIALUPUSA.NET> "Richard Harrison" wrote in message news:12633-43D10574-1718@storefull-3254.bay.webtv.net... > Congratulations Dr. Ace! > > You sure know how > > to trash a place! > > Best regards, Richard Harrison, KB5WZI > Richard, Yes, that's a fact. 73, Ace - WH2T Article: 221167 of rec.radio.amateur.antenna From: "Tom the Canuck" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> <174c$43d041ea$18d6b488$14817@KNOLOGY.NET> <1137785765.969348.81760@g14g2000cwa.googlegroups.com> <1137822271.315866.144350@g47g2000cwa.googlegroups.com> Subject: Re: How to earn money with PAYPAL!!!! 37 Message-ID: <22kAf.22374$xk1.621232@news20.bellglobal.com> Date: Sat, 21 Jan 2006 00:56:12 -0500 Harry C, For what it is worth, I stand behind you 100%. I hope you do not close your borders to your northern neighbours. Read my post just above yours. Tom the Canuck. wrote in message news:1137822271.315866.144350@g47g2000cwa.googlegroups.com... > GBrown, the fact that they couldn't speak fluent English may have > prejudiced my conclusion. It isn't very clear to me why the Social > Security offices need interpreters. After all, anyone who has been in > this country sufficiently long to seek Social Security benefits should > at least be conversant in English, since that is the language that is > spoken here. > > When you see many people who appear to be under the age of 30 and > cannot speak fluent English seeking SSI benefits, the red flag should > go up for everyone. Where is the Green Card? Damn, what was wrong with > the Ellis Island immigration procedure, and why did the US eliminate > it? At that time your entry into the US was judged on your health, > skills, and ability to provide for yourself and your family in the > United States. During that era, no one came to the US for a free lunch, > unlike today. > > Realize that unless we secure our borders and return to the strict > immigation policies of circa 1910, the US will become a human dumping > ground for misfits from the balance of the world, and constructive > citizens will no longer be able to support it and flee to other nations > who, for the above reasons, close there borders to other than those > that can contribute significantly to their country -- and for good > reason. > > I am pissed off because some of those "new arrivals" are immediately > able to collect larger benefits from Social Security than I who have > been paying into the system for more than 50 years! Yet, we wonder why > Social Security is about to go bankrup! Dhuh!!!! > > Sorry for the curmugenous attitude, but the pot of US money has > limitations, and I believe that it should first be utilized for the > benefit of US Citizens who have contiributed to the system for many > decades, and not be wasted on on freeloaders who have obviously never > made any contribution to the system. > > Curmudgeonly yours, Harry C. > Article: 221168 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: [question] current/voltage amplitude inducted in antenna Date: Sat, 14 Jan 2006 10:09:42 -0600 Message-ID: <5543-43C92246-711@storefull-3256.bay.webtv.net> References: Peter wrote: "What amplitude can it be?" A receiving antenna has a radiation resistance. The load which extracts most power is a conjugate match for the antenna. With radiation resistance perfectly matched to receiver input resistance, the radiation resistance becomes the Thevenin equivalent source resistance feeding an identical receiver input resistance. 1/2 the voltage induced into the receiving antenna is used to re-radiate energy received by the antenna. The other 1/2 appears across the receiver`s input resistance. For a professional explanation of this topic, see Kraus` 3rd edition of "Antennas" page 32. "All about antennas at a glance". Best regards, Richard Harrison, KB5WZI Article: 221169 of rec.radio.amateur.antenna From: "Dr.Ace" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> <174c$43d041ea$18d6b488$14817@KNOLOGY.NET> <1137785765.969348.81760@g14g2000cwa.googlegroups.com> <1137822271.315866.144350@g47g2000cwa.googlegroups.com> Subject: Re: How to earn money with PAYPAL!!!! 37 Date: Sat, 21 Jan 2006 02:18:39 -0500 Message-ID: <98d8f$43d1e047$4fc61f3$7169@DIALUPUSA.NET> wrote in message news:1137822271.315866.144350@g47g2000cwa.googlegroups.com... > GBrown, the fact that they couldn't speak fluent English may have > prejudiced my conclusion. It isn't very clear to me why the Social > Security offices need interpreters. After all, anyone who has been in > this country sufficiently long to seek Social Security benefits should > at least be conversant in English, since that is the language that is > spoken here. > > When you see many people who appear to be under the age of 30 and > cannot speak fluent English seeking SSI benefits, the red flag should > go up for everyone. Where is the Green Card? Damn, what was wrong with > the Ellis Island immigration procedure, and why did the US eliminate > it? At that time your entry into the US was judged on your health, > skills, and ability to provide for yourself and your family in the > United States. During that era, no one came to the US for a free lunch, > unlike today. > > Realize that unless we secure our borders and return to the strict > immigation policies of circa 1910, the US will become a human dumping > ground for misfits from the balance of the world, and constructive > citizens will no longer be able to support it and flee to other nations > who, for the above reasons, close there borders to other than those > that can contribute significantly to their country -- and for good > reason. > > I am pissed off because some of those "new arrivals" are immediately > able to collect larger benefits from Social Security than I who have > been paying into the system for more than 50 years! Yet, we wonder why > Social Security is about to go bankrup! Dhuh!!!! > > Sorry for the curmugenous attitude, but the pot of US money has > limitations, and I believe that it should first be utilized for the > benefit of US Citizens who have contiributed to the system for many > decades, and not be wasted on on freeloaders who have obviously never > made any contribution to the system. > > Curmudgeonly yours, Harry C. > Harry, I agree with you. The waves of human parasites flowing into this once great country are drowning our economy. SEE Life Long Welfare for Soon to be Citizens http://www.islam-online.net/English/News/2004-07/24/article04.shtml Another situation that comes to mind was the "Lost Boys" from the Sudan. The US flew them over here paid for their housing and all other expenses. I am not against charity but charity begins at home. We have homeless, jobless, disabled Vets, etc.. that are not taken care of. Why the hell should we as a country bring or allow to enter foreigners that only desire to leach off what little fat is left of our land. May God bless the U.S.A. Ace - WH2T Article: 221170 of rec.radio.amateur.antenna From: "Tom the Canuck" References: Subject: Re: How to earn money with PAYPAL!!!! 37 Message-ID: Date: Sat, 21 Jan 2006 02:04:17 -0500 "SINYpyro" <*removethis*vanquish@earthlink.net> wrote in message news:X9Vzf.3243$vU2.2707@newsread3.news.atl.earthlink.net... > Kill yourself? > Why kill yourself when you can stay alive and fight this crap. No need to resort to physical violence (I don't like the idea) but instead use our intelligence to fight back. Why not swamp the offender's inbox with e-mails. SUBJECT: "How to make a million dollars easily from your home" INSTRUCTIONS (body text): Send me $2.00 by mail and I will send you complete instructions to be rich quickly. Please include a stamped self-addressed envelope. (IMPORTANT: Get a PO Box for the address) ----------------------------------------------------------------------- Your snail mail reply: "WHAT TO SEND TO SUBJECT ON PAPER (they paid for it):" SNAIL-MAIL SUBJECT: (use this for your e-mail) How to make a million dollars easily from your home What to do to start:: SEND THIS E-MAIL: Send me $2.00 and I will send you complete instructions to be rich quickly. Please include a stamped self-addressed envelope. {Insert your address here} WHAT TO DO: Mail the above paper message when you have $2 and envelope. ---------------------------------------------------------------------------- - This can also work if you take out a classified ad in a local news paper. There should be at least 1,000,000 morons in a large metropolis. Just send the same info but change it to say 'take out a classified ad'. ---------------------------------------------------------------------------- - Why not sell 'solar powered cloths dryers' for $50. Ship the sucker a cloths line. Technically you are not in the wrong. It is 'solar powered' after all, unless it is a cloudy day. ---------------------------------------------------------------------------- - Give back some crap to the target who has been cross posting to various NG. I was amazed to learn I posted to rec.radio.amateur.* groups. Your replies were there as well. I may check them out, it has been a long time since I made an FM transmitter. ====================================================== {back to pyro for a moment} Just a thought, I know about the electric firing panel for pyro displays. Lots of wires and switches. Is there any need for an RF ignition system? It could cost a few more $$$ but you eliminate the long run of wires from the panel to the pyro items you want to ignite. A secure comm protocol would prevent ignition by 'outside' sources. A laptop could be added to control the timing of events.to be fired. A simple User Interface to make it moron proof. What do you guys think? Just looking for ideas. Start another thread if you like the idea. We can discuss details. I have made embedded systems for about the last 20 years. This idea is possible. ====================================================== Sorry, feeling a bit malicious tonight, (===pyro thought not included===) Tom the Canuck. P.S. $2 will NOT work in Canada. We have those $1 and $2 coins to deal with. (Maybe up the cost to $5 CDN) $50 should work out just fine. Article: 221171 of rec.radio.amateur.antenna From: "Tom the Canuck" References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> <174c$43d041ea$18d6b488$14817@KNOLOGY.NET> <1137785765.969348.81760@g14g2000cwa.googlegroups.com> <1137822271.315866.144350@g47g2000cwa.googlegroups.com> <6dydnXcJcZzMU0zeRVn-hw@gwi.net> Subject: Re: How to earn money with PAYPAL!!!! 37 Message-ID: Date: Sat, 21 Jan 2006 02:27:18 -0500 "GBrown" wrote in message news:6dydnXcJcZzMU0zeRVn-hw@gwi.net... > Harry, I understand your point, completely. I was getting at the fact that > how are we to judge who or who isn't eligible for SSI. I worked all my life > and it wont be long before I can step up to the SSI office and sign my > forms. I wish there were a way to weed out the imposters but you have to > start home. There are people in this country, citizens, that take full > advantage of the soft hearted liberals and reap the rewards. I really don't > know if there is a good fix to and old problem. > Gary Mr. GBrown, In a sense I do not care what creed, colour, or nationality a person comes from. We are all human and live on this tiny blue marble called Earth. {yes there are assholes in every group, even yours, ignore them, I do} Let us judge by what a person does, not where they come from. Does it matter? If you contribute to our "society" (needs improvement) they are fine, if they live off the labours of others I object. Perhaps we should adopt the thinking that we are all one people on this planet. Are you going to blast me because my parents came from Estonia? (If you don't know where it is, look it up) Ignorance and prejudice are rampant on our planet. Can we not do better? What about your "equality and liberty for all" in your constitution? Did that include owning slaves from Africa? Open your eyes, see the world for what it is, embrace other ideas from other cultures and learn from them. Tunnel vision is a downfall for the existence of mankind. This is what I think, you may thing otherwise. I can not stop you from thinking the way that you do, you can not stop me from thinking my way. Tom the Canuck. Article: 221172 of rec.radio.amateur.antenna From: John Westerlage Subject: About Benjamin Franklin and Lightning Message-ID: Date: Sat, 21 Jan 2006 12:59:19 GMT While researching lightning protection and grounding in general I stumbled across the following: < http://www.physicstoday.org/vol-59/iss-1/p42.html > Benjamin Franklin's groundbreaking (pun fully intended) work on the subject. john, N5DWI Article: 221192 of rec.radio.amateur.antenna From: "Bill Turner" Subject: Re: Vertical on a tower Date: 22 Jan 2006 07:23:08 GMT Message-ID: References: Cecil Moore wrote: > Guess I'll go > back to my 2x4 support system. Darn! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2x4s have served well for years. :-) Bill, W6WRT Article: 221193 of rec.radio.amateur.antenna From: References: <1137880377.666765.324890@g43g2000cwa.googlegroups.com> Subject: Re: comet vert?no radals Message-ID: Date: Sun, 22 Jan 2006 12:45:30 GMT An idea, so if one took a random length say 30 foot length of twin feed, stuck a big 50 ohm resistor on one end and a ballun to bring it to 50 ohm resonance at the other, in the tuner via coax. would it be 50 ohms wide banded because it sees the 50 ohm 'dummy load' at the far end as a match, and radiates a signal 'of sorts' from the twin feed. If one used the tuner to miss match the 'antenna' The worse the match the more signal would squirt from the feeder. Article: 221194 of rec.radio.amateur.antenna Message-ID: <43D38B6C.24B2290C@earthlink.net> From: "Michael A. Terrell" Subject: Re: How to earn money with PAYPAL!!!! 37 References: <1137709653.497618.151660@o13g2000cwo.googlegroups.com> <14990$43d04031$18d6b488$14336@KNOLOGY.NET> <1137784735.650874.68910@o13g2000cwo.googlegroups.com> <43D181DC.19682475@worldnet.att.net> <43D2B26F.E715A14B@worldnet.att.net> <5a773$43d2ba04$97d56b99$16471@ALLTEL.NET> Date: Sun, 22 Jan 2006 13:41:36 GMT Fred W4JLE wrote: > > I always answer them really loud, then I tell them to hold on while I get my > hearing aid. Wait about 5 minutes and say hello again really loud. If they > are still there tell them the batteries are dead and to hold while you get > new batteries. Wait 5 more minutes and once again loud hello, if they are > still there cuss and say you got the wrong batteries and their not > working... > > You get the idea, totally frustrate them. I have never had one wait beyond > the initial getting the hearing aid. Sometimes I let them get all the way through their spiel, then I tell them that it really sounds great and that if I ever get well enough to go back to work, I might be able to buy it It really pisses them off. ;-) Other times I just tell them right away that I am 100% disabled, and in too much pain to put up with them. Of course, being on the national "Do not call list" stopped almost all of those irritating calls. The only problem I have is some deadbeat is, or has given out my phone number when they bought crap on credit. I keep a list of these calls and if I get a second call from a company I scream at them while demanding that they leave me alone, or I will have a lawyer on their ass for trying to collect someone else's debt from me. The only ones too stupid to listen was "Countrywide" which was some kind of mortgage or lending company who had someone different call each time, from different phone numbers. They finally left a message on my answering machine with an "800" number stating that it was an emergency, but didn't identify themselves. It was their headquarters, and I really tore into them, informing them that I had repeatedly told their phone monkeys they had the wrong phone number, that I was a 100% disabled veteran, and that I was not going to put up with even one more phone call. I laughed and told them that if I did get one, that I would call friends at a TV station to have their local office investigated by their news department for violating a lot of different laws, and that I was going to turn over my hand written logs of all of their calls, along with their misleading telephone message. I asked what they thought that would do to their business in the area, just before I hung up my phone. I never heard from them again. :) -- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida Article: 221195 of rec.radio.amateur.antenna From: "Frank" References: <6NDAf.97704$AP5.43927@edtnps84> <43D3106E.4020100@comcast.net> Subject: Re: 8405a working and measuring resonance? Message-ID: Date: Sun, 22 Jan 2006 13:58:55 GMT "dansawyeror" wrote in message news:43D3106E.4020100@comcast.net... > Frank, > > The Smith Chart shows that a termination value other then 50 Ohms is > required to calibrate the 8405a to zero phase for the frequency and cable. > That said there are two zero points, I will have to think about the effect > of these on the measurements. Dan, I am not sure how you arrived at the above conclusion. The procedure should be as follows: Short the end of the coax at the antenna location, then adjust the line stretcher for a 180 degrees phase shift. This is your reference reflection coefficient of -1 (i.e. 1 < 180). Remove the short and verify the reflection coefficient is 1 < 0. Connect a known 50 ohm load, which should provide a return loss of > 30 dB. The angle of the reflection coefficient is irrelevant. If the return loss of the 50 ohm load is significantly less than 30 dB, then either your load is not very good, or you have poor coupler directivity. Attach the antenna, measure, and record, the magnitude and angle of the reflection coefficient. Repeat the procedure for all frequencies of interest. You will then be able to plot the result on the Smith Chart. At the frequencies you are working, which I believe is in the 100 to 200 MHz range, it is doubtful that the non-ideal short/load standards parasitics will effect the results significantly. I have done such measurements countless times, although with HP VNAs, which makes the procedure far less tedious. Hope this helps, Frank Article: 221196 of rec.radio.amateur.antenna From: John Ferrell Subject: Re: comet vert?no radals Message-ID: References: <1137880377.666765.324890@g43g2000cwa.googlegroups.com> Date: Sun, 22 Jan 2006 15:14:41 GMT On 21 Jan 2006 13:52:57 -0800, jgboyles@aol.com wrote: > >ml wrote: >> In article , ml >> wrote: >> >> > i see this month arrl magazine qst reviews a new hf comet verticle >> > that dosn't use radials >> > >> > i am just wondering how does this work? >> > >> > it specifies that its not a stelar performer has low swr but dosn't >> > explain the technology"" it uses to 'work' w/o radials >> > >> > >> > anybody know? >> > >> > >> > thanks >> >> i reamain eager for an answer to my question > > Just a guess, but I'll bet that thingey down at the bottom of the >antenna is a resistor. Although it says it doesn't need radials, they >would help, although they might mess up the broadbanded appeal of the >antenna. >Gary N4AST Is a resistor used in matching a bad thing? My intuition is that it is, but I have no math to back up the position. One of my current projects is to understand the matching problem for an electrically short vertical. Using EZNEC+, when I run the SWR function with the radiator (simulated real ground) I get an indication of Z = R + j. If I add an inductive load at the bottom of the radiator equal to the j value it brings the match into a reasonable range. At this point I have not grasped the relationship of the "R" in the equation. If I use the figure for R equal to 10% of the XL, the match gets even better, but not 1:1. 10% comes from the suggested estimate in the help file. Question 1: What is this "R" thing? I started out thinking it was series DC resistance and lower is better. My interpretation of the EZNEC results contradict this position. More "R" seems better. Question 2: Is this an effective method of matching a 50 ohm line to the vertical radiator? I do understand this is a math model and it ignores radiation from the inductor. Question 3: Looking ahead, I think the next matching technique should be an inductor in series with the ground end of the radiator and the ground. The 50 ohm line would feed a tap on the coil 50 ohms up from ground. Do I compute XL from the bottom to equal 50 or is this strictly a cut & try thing? I have yet to physically model anything with these tests but I am getting close to it. I know there are better matching methods than what I am attempting, this is an academic exercise for me! John Ferrell W8CCW Article: 221197 of rec.radio.amateur.antenna From: "Ralph Mowery" References: Subject: Re: Pulling Cable in Conduit Message-ID: Date: Sun, 22 Jan 2006 15:57:12 GMT "gb" wrote in message news:tqydneekV8fpOE7eRVn-uA@comcast.com... > "jimbo" wrote in message > news:HvKdnUnMwK5OOU7enZ2dnUVZ_tWdnZ2d@comcast.com... > >I am getting close to pulling some cable through a 1 1/4 inch PVC conduit > >that runs about 20 feet from the third floor attic to the basement. The > >contractor claims the conduit is a "straight shot" with no bends. I have > >three LMR240 cables with PL259 connectors on each end. And I would also > >like to pull a 450 ohm length of ladder line. (Measures about 1 inch.) And > >I would like to pull at least two 16 gage insulated control wires. > > > > Any advice would be appreciated. > > > > Thanks, jimbo > > > > A Google search should get you the electrical handbooks and codes (e.g. > NEC ) for the maximum fill for each conduit size. As a rough rule NEVER > fill a conduit more than 70% to 75%. > The NEC is mostly for wires for the AC lines. It will not apply for the antenna wires. The ladder line is not going to work too well in the conduit with the other wire. There is a minimum distance that it should be placed from other conductors. Article: 221198 of rec.radio.amateur.antenna Subject: Re: Pulling Cable in Conduit From: Ed References: Message-ID: Date: 22 Jan 2006 17:12:41 GMT > I am getting close to pulling some cable through a 1 1/4 inch PVC > conduit that runs about 20 feet from the third floor attic to the > basement. The contractor claims the conduit is a "straight shot" with > no bends. I have three LMR240 cables with PL259 connectors on each > end. And I would also like to pull a 450 ohm length of ladder line. > (Measures about 1 inch.) And I would like to pull at least two 16 gage > insulated control wires. > > Any advice would be appreciated. > I think you can get those three coax lines down the straight conduit if you stagger the PL-259 connectors, however, once you have a couple cables in the conduit, you may find there isn't enough room for a PL-259 to squeeze by, so you may need to remove the connectors, pull the cables and then reinstall them. Three LMR240s and two control cables are going to fill that conduit more than you realize! As far as the Ladder line goes, DON'T ! It will be nearly useless packed in with all that coax and wire as it needs several inches of SPACE around it to function properly, with no nearby metal objects. That coax braid in close proximity will drastically reduce its effectiveness. Ed K7AAT Article: 221199 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Vertical on a tower References: Message-ID: <8XPAf.21173$PL5.4948@newssvr11.news.prodigy.com> Date: Sun, 22 Jan 2006 18:13:24 GMT Reg Edwards wrote: > Height of tower. Approximately 30 feet. > Length of vertical radiator. 22 feet. > Number and length of radials. 4 x 22 feet. > Any loading coils? No, an SGC-230 at the base. > Imagine what might happen if the radials were removed. I imagined that and got very high angle radiation on some bands. The tower becomes part of the radiator. -- 73, Cecil http://www.qsl.net/w5dxp Article: 221200 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Vertical on a tower References: <1137915322.724857.201990@z14g2000cwz.googlegroups.com> Message-ID: Date: Sun, 22 Jan 2006 18:18:28 GMT nm5k@wt.net wrote: >>I'm putting a vertical back up for transmitting and will >>probably receive on my horizontal dipole. > > Why? Doesn't make sense. If the vertical is best for > transmit, it should be the best for receive 98% of the time. That's certainly not true at my QTH. The vertical has two extra S-units of noise on receive compared to my dipole. I'm assuming the two extra S-units of noise on receive won't affect my transmitted signal. When I had my 40m vertical up, I never heard any signal that was better received on the vertical. +12 dB of noise is virtually impossible to overcome in actual practice. > But almost all my GP's > had the radials attached to the mounting plate, which in > turn was mounted to the mast. Conductive mast? -- 73, Cecil http://www.qsl.net/w5dxp Article: 221201 of rec.radio.amateur.antenna From: Bob Bob Subject: Re: Pulling Cable in Conduit References: <7t97t11hullq3bo0qdrml0bb7u942hfnv8@4ax.com> <86GdnSMf7o9wM07eRVn-ig@comcast.com> Message-ID: Date: Sun, 22 Jan 2006 11:55:37 -0600 Yes a very negative effect and not a good idea.. If you look in the history of this NG you will see some numbers about minimum separation distance from other metal. If you really want to run a balanced feeder you can use two pieces of coax with the shields connected at each end. The Z will be twice that of the original coax. (I use this as a Q section on 20m feeding a loop of about 170 ohms) Dunno about losses in this case (which open wire feeder are great for reducing) and of course the Z is going to be kind of lower than 450r. Cheers Bob VK2YQA jimbo wrote: > > Thanks for the replies. The ladder line would be used when the other > lines were not being used. Does the proximity of other unpowered lines > affect the ladder line operation for receive and transmit? > > Thanks, jimbo Article: 221202 of rec.radio.amateur.antenna From: "Larry Gauthier \(K8UT\)" References: Subject: Re: Pulling Cable in Conduit Message-ID: Date: Sun, 22 Jan 2006 13:08:08 -0500 Jimbo, It's going to be crowded in that conduit, so don't rely upon gravity to get that stuff down the pipe. Three suggestions: 1. Buy a 25 foot electrician's steel snake (Home Depot, Lowe's, ...), use this to pull the wires through; or drop a length of poly line/guy string as a pull line. If gravity does not get the pull string through the conduit, tie a lightweight object to the line and suck/pull with a leaf blower or vacuum cleaner. 2. Stagger the pl-259's and open cable ends as much as possible so that this looks like a pointed, rather than a blunt, object going through the conduit. 3. When you're pulling the wires into the conduit, do your best at the feed point to keep the wires "straight" and not twisting into the conduit. This takes less space and permits you to do item #4 . 3. ADD A PULL STRING IN THE CONDUIT WITH THE WIRES! So when you're all done, three months from now, and you realize you just want to add one more little 4 conductor cable (or whatever!), you can do it without completely dismantling the cables. {been there, done that} -- -larry K8UT "jimbo" wrote in message news:HvKdnUnMwK5OOU7enZ2dnUVZ_tWdnZ2d@comcast.com... >I am getting close to pulling some cable through a 1 1/4 inch PVC conduit >that runs about 20 feet from the third floor attic to the basement. The >contractor claims the conduit is a "straight shot" with no bends. I have >three LMR240 cables with PL259 connectors on each end. And I would also >like to pull a 450 ohm length of ladder line. (Measures about 1 inch.) And >I would like to pull at least two 16 gage insulated control wires. > > Any advice would be appreciated. > > Thanks, jimbo > Article: 221203 of rec.radio.amateur.antenna From: Cecil Moore Subject: Re: Pulling Cable in Conduit References: <7t97t11hullq3bo0qdrml0bb7u942hfnv8@4ax.com> <86GdnSMf7o9wM07eRVn-ig@comcast.com> Message-ID: Date: Sun, 22 Jan 2006 18:27:37 GMT jimbo wrote: > Thanks for the replies. The ladder line would be used when the other > lines were not being used. Does the proximity of other unpowered lines > affect the ladder line operation for receive and transmit? Especially transmit. You will lose a lot of your transmitted power to the conductors surrounding the ladder-line. Ladder- line should be run a few inches away from anything. -- 73, Cecil http://www.qsl.net/w5dxp Article: 221204 of rec.radio.amateur.antenna From: "Bill Turner" Subject: Re: Vertical on a tower Date: 22 Jan 2006 17:52:38 GMT Message-ID: References: <1137915322.724857.201990@z14g2000cwz.googlegroups.com> nm5k@wt.net wrote: > Why? Doesn't make sense. If the vertical is best for > transmit, it should be the best for receive 98% of the time. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Nope. Verticals are notorious for picking up local man-made noise. Man-made noise starts out with random polarization but the horizontal component is quickly "shorted out" by the earth's conductivity, leaving only the vertical polarized component. This is why AM broadcast stations universally use vertical polarization; better groundwave coverage. They are not concerned with skywave or local noise. For skywave, either one works fine, but a horizontal antenna is quieter. Bill, W6WRT Article: 221205 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: HF-Ground Date: Sun, 22 Jan 2006 13:28:29 -0800 Message-ID: <11t7u80f9s1gi0a@corp.supernews.com> References: <1137679046.849697.239010@g44g2000cwa.googlegroups.com> Reg Edwards wrote: > > . . . . as demonstrated by program RADIALS2 > > which treats radials as transmission lines. As they truly are. >. . . I disagree. Transmission lines have two conductors. Radials don't. The fields from transmission lines are confined to the region between the conductors. The fields from radials can couple quite strongly, altering their performance a great deal. It might be possible to model a radial system as a system of coupled transmission lines. Is that what your program does? Roy Lewallen, W7EL Article: 221206 of rec.radio.amateur.antenna From: Bob Miller Subject: Re: Lightning Arrestor & Protection Of Receiver ? Message-ID: References: <94765$43d0b434$4e0bd10$27948@DIALUPUSA.NET> Date: Sun, 22 Jan 2006 21:37:04 GMT On Fri, 20 Jan 2006 04:58:4