Subject: GLOWBUGS digest 137

From: [email-masked]
Date: Thu, 21 Mar 1996 19:43:32 -0600 (CST)

GLOWBUGS Digest 137

Topics covered in this issue include:

  1) Inside the Russian Tube Industry
	by [email-masked]
  2) Tube Testing and Transconductance
	by "Barry L. Ornitz" <[email-masked]>
  3) Re: Glowbuggite/Boatanchorite 3579.545 funzies
	by [email-masked]
  4) Re: Glowbuggite/Boatanchorite 3579.545 funzies
	by [email-masked]
  5) Re: ....funzies
	by [email-masked]
  6) 1937 edt. of amateur radiotelephony...sold
	by robert fowle <[email-masked]>
  7) FCC rules on the Web (Was Funzies)
	by "Dennis L. Wade" <[email-masked]>

----------------------------------------------------------------------

Date: Wed, 20 Mar 1996 22:23:41 -0500 (EST)
From: [email-masked]
To: [email-masked]
Subject: Inside the Russian Tube Industry
Message-ID: <[email-masked]>

As an afterthought to my post about Western Electric tubes back in
production in the States, I should mention that Volume 6, Number 4
of the aforementioned magazine, "Glass Audio", has an in depth
article about the Russian tube industry, "Inside the Russian Tube
Industry" by Eric Barbour.  This is a VERY interesting article
that features lots of small-signal and power RF tubes. Manufacturers
featured include Svetlana, Ryazan, and Ulyanov.  I believe
copies are still available from the publisher, Audio Amateur
Publications, PO Box 176, Peterborough, NH 03458, 603-924-9464.
Also, Mr. Barbour, the author, has available a list of Russian and
Soviet tube types and their Western equivalents.  It is available
for $5.00, post paid, from Eric Barbour, 555 El Camino, #105,
Sunnyvale, CA 94087.
                        73, Mike

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                  %
% Michael A. Burke, Synetics Consultants           %
% PO Box 439, 11 Scenic Dr, Westminster, MA 01473  %
% 508-874-0908  [email-masked]                     %
%                                                  %
% With apologies to Will Rogers, "I never met a    %
% vacuum tube I didn't like" (well, almost never). %
%                                                  %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

------------------------------

Date: Thu, 21 Mar 1996 10:48:11 -0500 (EST)
From: "Barry L. Ornitz" <[email-masked]>
To: [email-masked]
Cc: Glowbugs Mailing List <[email-masked]>
Subject: Tube Testing and Transconductance
Message-ID: <[email-masked]>

Michael Burke wrote about tube testing - emission vs. transconductance,
and he said the the Eico 667 used a different technique.  I would like to
ask how does the Eico really work? 

Transconductance (sometimes with the adjective mutual added) is merely the
partial derivative of the plate current with respect to the grid voltage
with all other parameters held constant.  This is normally done by
measuring the AC plate current with a small AC voltage on the grid.  If
the AC grid voltage is relatively small, the transconductance is the AC
plate current divided by the AC grid voltage and is measured in recprocal
ohms or Siemens.  But you can also do the same measurement with DC.  Shift
the grid voltage slightly and measure the shift in plate current.  The
transconductance is then the change in plate current divided by the change
in grid voltage.  Both methods measure transconductance but one is an AC
measurement and the other is a DC measurement.  Although rarely used, it
is possible to measure the transconductance of the screen and other grids
of a tube too. Since low frequency AC signals are used, capacitive effects
on the transconductance are generally ignored.  [My Hickoks measure at 60
Hz; I have a manual for a Heath that measures at 5 kHz.]

Probably the best test of a tube, other than by direct substitution in the
circuit in which it is used, is the power output method.  In this case,
the tube is biased for normal operation and an AC grid voltage is applied
to simulate the normal drive level.  Power output into a load is then
measured.  This power level is indicative of the overall performance of
the tube - a combination of emission and gain.  This particular test is
excellent for testing audio output tubes.  Distortion might also be
measured if this is a critical parameter.  Doing this test at radio
frequencies, however, is difficult so with RF power tubes substitution is
still the best test. 

Curve tracers are very useful for illustrating the nonlinear
characteristics of tubes which is the reason that many universities bought
them.  Other than their use to a tube designer (someone who designs tubes
themselves, not tube-based circuits), virtually no one else had a use for
them.  The characteristics of a particular tube are generally very tightly
controlled.  These basic characteristics are published and they do not
normally change much as the tube ages (although gain does drop off with
decreased emission and loss of vacuum causes other problems).  Early
solid-state devices, on the other hand, showed considerable spread in
their characteristics so transistor curve tracers are much more popular.
[I think a 5% decrease in transconductance may classify a tube as suspect,
but early transistors as manufactured could show as much as a 2000%
variability in their current gain!]

		73,  Barry L. Ornitz  WA4VZQ  [email-masked]

------------------------------

Date: Thu, 21 Mar 1996 12:31:19 -0500 (EST)
From: [email-masked]
To: [email-masked] (Sandy Blaize)
Cc: [email-masked] (), [email-masked],
Subject: Re: Glowbuggite/Boatanchorite 3579.545 funzies
Message-ID: <[email-masked]>

There were a bunch of fellers on last night for the continuing saga
of the woebegone, forlorn, erstwhile lost glow-in-the-dark rigs of
normal and homebuilt timbre on the fine QRG of 3579.545 at 0300/0400/0500/
0600Z.  More of the crew should fires up their bottleburners and join in
on the fun.  After all, why have such ancient monsters around, if they
don't puff and smoke and spark and generally burn a hole or two in the
ether, in the wee small hours.....(:+}}.....

Last night had eveything from a modern rig (his bottleburner was not up
to it last night), to the venerable Viking, Ranger, TCS-13, and Big Bertha
Radiomarine, to a fine breadboard puffer using a 6A6 MOPA circuit,
self-oiscillatioryable or tv rox ringing.  All were in fine form, and
well heard across the ether.

So, join in if you can, and keep yer filaments warm, and yer bottles
stoked, fer some fine rattle 'n banging on the ol brass monkey.

> Bob,
> 	Well....how did the 6A6 rig do as an MOPA last nite?

Sounded great MO or XTAL.  XTAL was more stable, but MO was not at all bad.

> Plugged grid coil in xtal socket making the oscillator a Push-pull
> TPTG oscillator driving the push-pull/parallel 6A6 final.  It ran
> about 350v. @ 50 ma. input. (17.5 watts?)

17.5 watts makes for a fine puffer at 1000 miles distant.

> 	I found my "article" on the oscillator using a single 860
> tetrode.  I may eventually build this beast.  It would probably thump
> out a distinctive signal!

Would that be Dow's classic article from about 1933 QST?  Good reading
for anyone thinking about electron coupled oscillators (Dow used a 75 watt
tube for his, and likewise did the Navy in their big rigs such as TBK).

> 	Looks like the group is starting to gather.  Haven't had 4-5
> station CW round-tables in YEARS!

I am hoping the round-table format will work out.  It is not sufficiently
extreme to require a net control type, so the round table seems to work well.
I am not font of nets, and it has been 15 years since I have run one, so my
netetiquette is probably quite rusty.

> 	I've noticed that here about 0430-0500 until about 0600-0630
> or so 75/80 meters seems to go "bonkers" for a while.  The skip lengthens
> out and the QSB/flutter sets in, then, magically, a little past midnite,
> things stabilize again.  Weird!

That is the skip heading west across the continent.  It can be used to
advantage in determining where you want to work, but will put some folks
in rf sinkholes for a while.  But, everyone was a solid 559 or better,
even with W1AW nearby (no sweat to the regenerator, it just clips it out)
and the TV buzz was not much, so all, in all, it was a good working
QRG for the bottleburners, and TV rocks are cheap and easy to find.
I had three receivers going for comparisons --- the venerable regenerator
RAL, a NC-100A, and an R-388.  The RAL was by far the best for operating.
The R-388 was more sensitive, but not any better at filtering (the basic
IF was too broad, and the xtal filter still did not drop everything out
as well as the RAL did).  The NC-100A was sensitive, but way too broad
in tuning to be usable except in a pinch.  It did have great audio
quality tho, much better than the R-388 even, but the bandwidth was the
pits --- way to wide, with only 3 if cans.  Although the RAL suffers
from static crashes more than anything else, it still is a razor tuner,
compared to almost anything else, if you get used to its null dial
calibration.....(:+}}.....

> 	The strangest propagation I ever witnessed, was near or on the
> equator in the Amazon area.  We had about a 400 mile path from offshore
> near Amapa to Belem, Brasil.  12 Mhz would open for about an hour in the
> afternoon.  8 Mhz was sketchy sometimes 4 mhz at night.  WOM in Miami
> roared in on 8 mhz for a couple of hours around 8 PM-10 PM
> Belem time (GMT -3 hours I think).  Static levels very high.  The damned
> barograph made a 'sine wave' recording, almost exactly the same pressure
> changes every day.  Onshore in Belem, you could set your watch by the
> afternoon showers!

Well, when I monitor the 4/6/8 mhz bcsts and tfc lists for background music,
I notice the same thing.  WCC on 6 mhz will be QSA 5 and on 8 mhz it will
be QSA 3 and then a little later the reverse.  FYI, any folks wanting to
monitor good mill copy wx/px bcsts, we have lost WLO to modernity, and the
only wx/px comes from WCC and WNU that I can hear and that is irregular.
I will always be missing those snappy precise 31wpm mill copy runs of the
tfc lists and wx from Mobile, every hour on the hour, 24 hours a day.....
WCC runs a wx bcst at noon daily, and WNU at about an hour earlier, but
the only press run seems to be on WCC on sunday after the wx.  I still love
to listen to the background mill copy on a good snappy wx bcst whilst
puttering around the shack.  They are always loud enough even to use as
an alignment source for particular bands.

> 73,
> Sandy W5TVW

73/ZUT Sandy and the other fellers aboard for the watch.  It is great fun,
and gives us all a chance to stoke up the bottleburners an' plys we the
ethers fer a fine watch aboard the crackle an' din o' 200 metres an' down.

DE NA4G/Bob UP

------------------------------

Date: Thu, 21 Mar 1996 14:01:36 -0500 (EST)
From: [email-masked]
To: [email-masked] (Roy Morgan)
Cc: [email-masked] (), [email-masked],
Subject: Re: Glowbuggite/Boatanchorite 3579.545 funzies
Message-ID: <[email-masked]>

> >Well, when I monitor the 4/6/8 mhz bcsts and tfc lists for background music, 
> >WCC runs a wx bcst at noon daily, and WNU at about an hour earlier, but
> >the only press run seems to be on WCC on sunday after the wx. 

Since WLO left us, the only run I have from memory is WCC daily at
1700UTC with the WX from the National Weather Service (High Seas, Offshore,
Caribbean, Gulf).  QRG 6376/8630/13xxx/16xxx.  From where I am 6376 and
8630 are the best.  The American Radio Association Free Press (a shipboard
radio officers union newspaper) follows Sunday at 1800UTC.

I have WNU and KFS skeds at home, but don't remember them right off.
WNU is about an hour before WCC, but I don't have the QRG on the top of the
ol greymatters.  I found WNU's sked accidently, while playing with the
NC-100 trying to get it up and running.  I will sorely miss WLO's
every hour on the hour 24 hours a day skeds.  Oh, well, so much for progress.

> SRI to have to ask, but can you tell me the frequencies for these guys?
> 
> Maybe a short summary of frequencies/times for those of us who haven't plied
> the ethers in such a manner as you-alls.

The frequencies are in Title 47 CFR80, in a huge table, but each station
usually broadcasts its schedule a time or two daily.  Cruise 4100-4600,
6100-6600, 8200-8700, 12500-13500, 16000-17000, and 22000-23000khz.
It is a great way to check, quickly, any boatanchor receiver, since most
of these stations run at least 1.5kw and many 10kw.
 
> Thanks.
> (I'm gonna drag out the RAL on Saturday and see what it'll do!)

Hey..... GoForIt!

DE NA4G/Bob UP

------------------------------

Date: Thu, 21 Mar 1996 15:02:37 -0500 (EST)
From: [email-masked]
To: [email-masked] (Dalton McCrary)
Cc: [email-masked] (), [email-masked],
Subject: Re: ....funzies
Message-ID: <[email-masked]>

> Bob,
> You speak of 'Tytle 47 CFR80'.  Just what is this publication?

This is the FCC Rules and Regulations.  Part 15 is unlicensed operation.
Part 97 is amateur operations.  Part 80 is commercial shipboard radio
operations.  There are tables of frequency authorizations and modes in
the various sections, as well as detailed rules of operations, testing,
licensing, etc.  The tables of frequencies are an excellent source of
what goes on where in the HF bands.

> Could it be found over the web?

Don't think so.  But any good library worth its salt has a set in the
government docs section.

> 73, Dalton
> N4OYS

73/ZUT DE NA4G/Bob UP

------------------------------

Date: Thu, 21 Mar 1996 15:33:04 -0500 (EST)
From: robert fowle <[email-masked]>
To: [email-masked]
Subject: 1937 edt. of amateur radiotelephony...sold
Message-ID: <[email-masked]>

the book is gone..

===========================================================]-[->
Robert Fowle
The HAMMARLUND Historian
Ph. voice or fax  517-789-6721
1215 Winifred
Jackson, Mich. 49202-1946
E-mail at: [email-masked]
                              HAMMARLUND LITERETURE WANTED
===========================================================]-[->

------------------------------

Date: Thu, 21 Mar 1996 15:50:56 +0000
From: "Dennis L. Wade" <[email-masked]>
To: [email-masked]
Subject: FCC rules on the Web (Was Funzies)
Message-ID: <[email-masked]>

Cornell has an experimental server loaded with the entire Code of 
Federal Regulations, including of course the Amateur Service Rules, 
all of which is searchable.  Point your browser to:

http://www.law.cornell.edu/regs.html

Have fun!

Dennis
KG6ZI

------------------------------

End of GLOWBUGS Digest 137
**************************