Subject: glowbugs V1 #165
glowbugs Friday, November 28 1997 Volume 01 : Number 165
Date: Thu, 27 Nov 1997 11:35:00 EST
From: ne1s@juno.com (Larry Szendrei)
Subject: 805 vs. 211
Someone on the list had asked me if the 805 was electrically the same as
a 211, and was contemplating the use of either tube in a Hartley.
Unfortunately, just as I had completed my response and tried to send it,
my computer locked up and I lost both the reply and the message I was
replying to. So, I'll post my answer to the list.
The 211 is not electrically identical to the 805. The 805 is a bit
heftier (125W vs. 100W plate dissipation for the 211) and the mu of the
805 is ~50 compared with 12 for the 211. That being said, both are fine
tubes in a Hartley Glowbugge application, and the difference in
characteristics will probably not be noticed, except the optimum value of
grod leak might be slightly different. I have a 1950 ARRL handbook that
lists characteristics and typical operating conditions for practically
any transmitting tube in existance at that time, and it's a great
resource.
Keep on glowin'...
Larry (NE1S)
Date: Thu, 27 Nov 1997 11:35:00 EST
From: ne1s@juno.com (Larry Szendrei)
Subject: Tinkerin' with the TNT and 1929 AWA QSO party
Well, I've been off work since last Saturday , and have been putting some
time in on the TNT rig in preparation for the 1929 Bruce Kelley Memorial
QSO party coming up the next two weekends (6pm Sat. to 6pm Sun (EST), Nov
29-30 and Dec 6-7). Until now, this rig has been confined to 160M, and
running pp 801A's. The QSO party is on 80M, so I wound up a copper tubing
plate coil (3/16" tubing, 12T, 2.5" dia.). I had ballparked a grid coil
for 80M (or so I thought) a few years ago.
Upon smoke testing the lash-up with the new" coilage", I found it was
resonating on 2.8Mc, and concluded I probably wouldn't do well in the QSO
party on that frequency. (I had to add quite a bit of capacitance across
the plate tank to get it to oscillate at all.) I took several turns off
the grid coil, and now she's optimized for the low 100 Kc of 80M.
Since the "contest" rules require that the tube(s) in the transmitter
must be a type in existance in 1929, the 801A's were out. So I borrowed a
pair of '45's from an old broadcast radio chassis I have, and plugged
those in. The rules also limit plate input to 10W, so I reduced my plate
voltage from 400 (my power supply uses a voltage divider to do this -
it's a reincarnated Kolster power supply/audio ouput chassis using the
original power transformer). I know that this breaks all the (other)
rules, because regulation is lousy, but the end result seems to be
acceptable: the note is a bit chirpy, but not too bad, as long as the
loading is kept light. In this event, I'm sure there will be even more
"interesting" sounding signals! Key down I've got ~265V @ 35 mA for about
9W input, and as far as I can tell I'm getting 2-3W out to the aerial
(antennas won't work right with these rig, hi!).
Hope for good conditions, and to see some of you on 3580 - 3595 Kc this
weekend!!!
73 fer now...
Larry (NE1S)
Date: Thu, 27 Nov 1997 08:49:49 -0800 (PST)
From: Ken Gordon <keng@uidaho.edu>
Subject: Re: Push-pull Hartley...
On Thu, 27 Nov 1997, Roderick M. Fitz-Randolph wrote:
> >Bob (or anyone else for that matter), got any schematics for a Push-pull
> >Hartley?
> >
> >Ken W7EKB
> _________________________________________________________________________
> Now, I'd be interested in that answer, as well!!
>
> Rod, N5HV
> w5hvv@aeneas.net
I DID find a push-pull self-excited oscillator circuit in my old Nilson
and Hornung "Practical Radio Communications" handbook, but it doesn't look
quite like a Hartley since the cathodes are grounded directly and the tap
on the coil goes to the grids.
I would be happy to send this circuit diagram and description to anyone
for an SASE.
Address below on the left.
Kenneth G. Gordon W7EKB College of Mines and Earth Resources
226 N. Washington St. //or// University of Idaho
Moscow, Idaho 83843 Moscow, Idaho 83844
(208)-882-8745 (208)-885-6133
Great Highland Pipes, Amateur Radio, Electronic Consulting, Home-Schooling
Traditional Roman Catholic
My PGP Public Key Upon Request.
Date: Thu, 27 Nov 1997 11:34:50 -0600 (CST)
From: Kevin Pease <hamradio@mm1001.theporch.com>
Subject: 15 meters open
Guys I just worked Guyana on 15 meters with my HT-37 and L4 to a verticle.
The band is open today. Pretty good signals alover the world. I also
worked bermuda.
Kevin Pease
WB0JZG
Mount Juliet, TN.
Date: Thu, 27 Nov 1997 18:52:05 EST
From: ne1s@juno.com (Larry Szendrei)
Subject: Re: Tinkerin' with the TNT and 1929 AWA QSO party
Hi Sandy,
Times are as I stated, 6PM EST Sat. to 6PM EST Sun for the next two
weekends.
Freq. is 3580 - 3595 Kc.
Exchange RST, year & type of transmitter, and power input. I'm not sure
if "year" means the "style year" or the year the transmitter was actually
constructed. Maybe another AWA member on the list (BA Bob?) can enlighten
us?
Quoting from page 39 of November's AWA Journal:
"The 1929 QSO Party is open to members using transmitters of 1929 or
earlier vintage. These may be self-excited types such as the Hartley,
TNT, push-pull tuned-plate-tuned-grid, etc. The MOPA transmitter is also
acceptable. The power input must be 10 Watts or less. Participants are
encouraged, but not required, straight keys and regenerative or other
vintage receivers."
I'm not sure to interpret this to mean that contest participation is only
open to AWA members???
Logs, citing equipment used, are to be sent to John Rollins, W1FPZ HC33,
Box 150, Arrowsic, Maine 04530.
I also see in the same issue that the AWA now has a website at
http://www.ggw.org/freenet/a/awa/. Haven't visited yet, but will check it
out soon.
73,
Larry (NE1S)
On Thu, 27 Nov 1997 21:24:37 +0000 Sandy W5TVW <ebjr@worldnet.att.net>
writes:
>
> Larry,
>
> You got the contest poop? (times, exchanges, etc.) I'll have
>to put my
>'10 Hartley on the air!
> 80 has been pretty good lately!
Date: Thu, 27 Nov 1997 20:24:15 -0800 (PST)
From: Ken Gordon <keng@uidaho.edu>
Subject: PP oscillator circuit...
I have re-drawn this circuit (from my 3rd edition "Practical Radio
Communications" by Nilson and Hornung.
Anyone wanting a copy, SASE (one stamp) to address below on the left.
Anyone have a decent Hartley PP oscillator schematic?
Kenneth G. Gordon W7EKB College of Mines and Earth Resources
226 N. Washington St. //or// University of Idaho
Moscow, Idaho 83843 Moscow, Idaho 83844
(208)-882-8745 (208)-885-6133
Great Highland Pipes, Amateur Radio, Electronic Consulting, Home-Schooling
Traditional Roman Catholic
My PGP Public Key Upon Request.
Date: Thu, 27 Nov 1997 22:42:13 -0800 (PST)
From: Ken Gordon <keng@uidaho.edu>
Subject: PP Osc. Transmitter...
I have finished drawing it with GCADD. From my "Practical Radio
Communications" book circuit, I added a keying circuit (one cap and a
key), and an antenna coupling circuit (one inductor, a tuning cap, and a
flashlight bulb). Then I made a parts list.
Now to see if it will work.
Do you guys remember our discussion a few months ago about the 15 watt
12AX7 ?
Ken W7EKB
Date: Fri, 28 Nov 1997 10:01:12 -0500 (EST)
From: EWoodman@aol.com
Subject: Tuned Plate-Tuned Grid Osc
I'm sitting here looking at a picture and schematic of a tuned plate - tuned
grid transmitter from 1930. It's built on a board with a big copper tubing
coil on each end and two tuning caps. In the middle it has one of those 204A
horizontally mounted triodes. Looks really nice.
But here's the scary part.............2500 volts on the plate and draws
200ma!!!!! Those guys were crazy! Did people actually run open breadboard
rigs like that? Don't suppose that meets the new regs for rf exposure.
By the way, was someone looking for a push-pull schematic? I've got one for a
push-pull TNT rig.
Happy Thanksgiving Eric KA1YRV
Date: Fri, 28 Nov 1997 09:34:39 -0600 (CST)
From: Bob Roehrig <broehrig@admin.aurora.edu>
Subject: Re: PP Osc. Transmitter...
On Thu, 27 Nov 1997, Ken Gordon wrote:
> Do you guys remember our discussion a few months ago about the 15 watt
> 12AX7 ?
I remember it, not much about what was said though. I think a 12AU7
would be a better choice - more than double the plate power ratings.
"No one is listening until you make a mistake"
E-mail broehrig@admin.aurora.edu 73 de Bob, K9EUI
CIS: Data / Telecom Aurora University, Aurora, IL
630-844-4898 Fax 630-844-5530
Date: Fri, 28 Nov 1997 07:53:17 -0800 (PST)
From: Ken Gordon <keng@uidaho.edu>
Subject: Re: PP Osc. Transmitter...
> > Do you guys remember our discussion a few months ago about the 15 watt
> > 12AX7 ?
>
> I remember it, not much about what was said though. I think a 12AU7
> would be a better choice - more than double the plate power ratings.
Or a 12BH7. :-)
Ken
Date: Fri, 28 Nov 1997 10:47:01 -0500
From: Steve Modena <ab4el@MindSpring.com>
Subject: Please help this person
I received the following note (see below) at my Website where I
"rebroadcast" BOATANCHORS
and GLOWBUGS via http://SunSITE.unc.edu/modena/hamradio.html.
Please help Andre out by email ( i.e. do not reply to me. :^)
- --
73/Steve/AB4EL
- -----------------------Cut Here---------------------
>>From: andre <andre@italnet.com.br>
Dear Srs:
I'm a research in audio tube circuits and need informations(datasheets,
pinoouts, etc) of the next tubes:
6111
EC760
DC762
I would built news microphones and desire test this small tubes in my
new projects.
What the directions to take this informations?
- --
Whith my best regards, thanks a lot Andre from Brazil
andre@italnet.com.br
Date: Fri, 28 Nov 1997 14:30:23 -0500 (EST)
From: rdkeys@csemail.cropsci.ncsu.edu
Subject: Re: Tuned Plate-Tuned Grid Osc
>
> I'm sitting here looking at a picture and schematic of a tuned plate - tuned
> grid transmitter from 1930. It's built on a board with a big copper tubing
> coil on each end and two tuning caps. In the middle it has one of those 204A
> horizontally mounted triodes. Looks really nice.
Yup.... That was quite common amongst the ``well heeled'' hams of that
era. The Headquarters station ran just such a set for a couple of years
on 80M, until a flood wiped the station out, if memory serves me correctly.
It is shown in some of the QST's and handbooks of the early 30's.
On a big double ended tube like the '04A, a Hartley was sometimes
impractical because of long lead length. The use of a split transmitter
such as a TPTG or a TNT circuit allowed the tube to be mounted on a long
board, or upside down vertically (remember to hang '04A's upside down
so the filament won't sag, if vertical) and have the shortest possible
tank leads. Things like the 849 and even the 833 lend themselves well
to the TPTG circuit.
> But here's the scary part.............2500 volts on the plate and draws
> 200ma!!!!! Those guys were crazy! Did people actually run open breadboard
> rigs like that? Don't suppose that meets the new regs for rf exposure.
Yup, folks ran those things, very carefully. Technically, these days,
the things need to be behind a panel enclosure of some kind (Nat. Elect.
Code), with all controls grounded for DC and AC. Just be careful if
you run one that big, open. Even ol' Boatanchor Bob gets a tad timid
when the plates get beyond 1 keelovoltie.
> By the way, was someone looking for a push-pull schematic? I've got one for a
> push-pull TNT rig.
Good, saves the grid circuit tank capacitor requirement. TNT's are
a tad more fussy to tune, since the grid coil is actually a very low
Q tank composed of strays and a poor Q coil. That is why it is working
as a Tuned Not Tuned set..... the grid circuit is Not Tuned (other than
a coarse approximation of strays and the low Q coil). A fully tuned set
Tune Plate Tuned Grid (TPTG) is usually better, if you have a second
capacitor available for the grid circuit. They are easier to control
and set compared to the TNT variety. My OM swore by the TNT circuit,
though, in the early 30's, but I have never had good success compared
to Hartleys or TPTG circuits, with them. The TNT's work, but can be
REAL squirrely if you are not very careful. There is a lot of fiddlin
to get the grid coil on a TNT set ``just right''. The Hartleys are rock
solid, all the time. One of these days I will try a Colpitts and an
Ultraudion circuit and see how they compare with the Hartleys and TPTG's.
Well, Sandy and I were on with the Hartleys last night at around
0600Z, where were the rest of the crewe????????? I worked around
half a dozen niteowls with Grandma Hartley and the regenerator, maybe
5 wattoes de ethere output, into a random 66 foot wire sort of slung
up into a tree. Surely others can do likewise? Comments Sandy?????
Beat the bushes.... round up the crewe..... etc.....(:+}}.....
All hands listen up on 3585-3595 this weekend for the AWA boys and
their 1929 style contest. There are some ``real gutsy and lusty''
signals there. Sadly Bruce Kelley's primary keyed set will probably
not be heard, unless one of the AWA crew runs it up. That thing had
the finest bell tone keying you have ever heard on a self controlled
oscillator. If I had not let my membership lapse, I would be there
with ol' Grandma Hartley and Twinnie Triode. Do listen in, tho, for
some funzies signals.
Bob/NA4G
End of glowbugs V1 #165
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