Subject: GLOWBUGS digest 342

From: [email-masked]
Date: Tue, 5 Nov 1996 09:40:35 -0600 (CST)

GLOWBUGS Digest 342

Topics covered in this issue include:

  1) Re: What is a 10Y?
	by "Scott Alfter" <[email-masked]>
  2) Re: What is a 10Y?
	by [email-masked]
  3) Re: 3A4 Regen RX in Sep 1995 CQ
	by [email-masked] (Jeff Duntemann)
  4) Printed Circuits that Glow
	by [email-masked] (Jeff Duntemann)
  5) Another 10Y description
	by Paul Bernhardt <[email-masked]>
  6) 6BM8 tubes
	by [email-masked] (Murray Kelly)
  7) Re: Printed Circuits that Glow
	by [email-masked] (Lee Richey)
  8) Re: Printed Circuits that Glow
	by "Brian Carling" <[email-masked]>
  9) Re Glowbugs admin ... please read
	by [email-masked] (Peter Holtham)
 10) "The Ocean Hopper" Magazine
	by "James P. Rybak" <[email-masked]>
 11) Reprint of '29 and '34 Handbook chapters
	by "Deane D McIntyre"  <[email-masked]>
 12) Re: Reprint of '29 and '34 Handbook chapters
	by [email-masked] (michael silva)

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

Date: Mon, 4 Nov 1996 07:51:40 -0800
From: "Scott Alfter" <[email-masked]>
To: <[email-masked]>
Subject: Re: What is a 10Y?
Message-ID: <[email-masked]>

On Sun, 3 Nov 1996, Gordon Gekko <[email-masked]> wrote:
> I just found an old box of tubes from my childhood days, and amongst
> the treasure trove of 6V6, 6AG7's and the like is a couple of
> an 'antique' tubes labeled '10Y'.  4-pin base, and about the
> size of the largest 6L6 package.

My '63 GE tube manual lists a type 10 tube as a filament-type power
amplifier triode with the following specs:

service: class A amplifier
pinout: filament on 1 and 4, grid on 3, plate on 2
filament power: 7.5V, 1.25A
max. B+: 425V
max. plate dissipation: 12W
power output: 1.6W
load impedance: 10.2k-ohms
grid bias: -40V

---
Scott Alfter
[email-masked]

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

Date: Mon, 04 Nov 1996 10:52:11 -0500
From: [email-masked]
To: [email-masked]
Subject: Re: What is a 10Y?
Message-ID: <[email-masked]>

Gordon Gekko <[email-masked]> asked:

>I just found an old box of tubes from my childhood days, and amongst
>the treasure trove of 6V6, 6AG7's and the like is a couple of an 
>'antique' tubes labeled '10Y'.  4-pin base, and about the size of the 
>largest 6L6 package.
>Does anyone know what this tube is and have any good GB ideas for it?

According to my notes, the 10Y is a type 10 with a low-loss base, which
helps it perform better at higher frequencies.  The 10 is 7.5 volt
filamentary power triode, used for audio and RF purposes - as a modulated
oscillator and regenerative detector.

I'd be interested in any ideas GBs come up with for these, too.  Take a
chunk of current in the filament, tho.
 
John Michael        [email-masked]

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

Date: Mon, 4 Nov 1996 09:14:47 -0700
From: [email-masked] (Jeff Duntemann)
To: [email-masked]
Cc: [email-masked]
Subject: Re: 3A4 Regen RX in Sep 1995 CQ
Message-ID: <[email-masked]>

>One final comment: The tuning is really NON-linear. 80 meters is fairly
>easy to tune but 40 meters is quite tightly packed near the high end of the
tuning range of the cap. I think what I will end up doing is re-designing
the tank circuit to cover just 80 meters with a lot more bandspread
>using a smaller cap along with a bandspread cap. I really don't know how
>anyone can actually use this rig on 40 meters the way it performs built
>according to the article. 80 meters might be OK but 40 is really pushing
>the envelope of reality.

If at all possible, try to find a constant-wavelength or constant-frequency
variable for the tuning cap, in case you're using a constant capacitance cap
for tuning.  (These are the caps having the rotor shaft offset from the
center of the plates, so that the decrease in capacitance as the plates are
de-meshed is rapid at first, and then tapers off to a slow rate as more and
more of the rotor is removed from the stator.)

Every time I've used a constant-capacitance variable for main tuning I have
nothing but trouble with "bunching" at one end of the cap's range.

Good luck and let us know if you have further success improving the circuit.
It would still be worth sending a summary of your enhancements to QST for an
article that recent, and maybe they'll publish it in "technical
Correspondence".  They may not publish it, but it can't hurt to try.

--73--

--Jeff Duntemann KG7JF
  Scottsdale, Arizona

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

Date: Mon, 4 Nov 1996 11:00:39 -0700
From: [email-masked] (Jeff Duntemann)
To: [email-masked]
Subject: Printed Circuits that Glow
Message-ID: <[email-masked]>

Hi gang--

Just wanted to take the pulse here: What do y'awll think of tube circuits on
PC boards?

I'm going to breadboard my "standard" 6AG7/6L6 transmitter shortly, and
after that I had the notion of creating a printed circuit board for it.
I've never done a transmitter on PC board before, but it was done a lot in
commercial rigs at the end of the tube era.  (I believe the Heath Single
Banders were bottles-on-PC-board, in fact.)  I'd love to see more clubs
involve novices in the building of tube rigs for CW, and club projects these
days are almost always PC board centered.

The sockets are available from AES and other places, because octal-based
relays are used even today.  Having a PC board would make it easier for
beginners to assemble correctly, which is one of my main goals.  I work with
a place in Oregon that makes good-quality boards inexpensively, and maybe we
could even prevail on one of the kit outfits to produce a kit.  My vision is
a circuit board the size of the chassis bottom plate, bolted to the inverted
chassis with the traces on the underside to keep B+ out of the way.  The
bottom plate then becomes the front panel.  Or, with some cleverness, I
could mount the tuning caps inside the chassis and not bother with a
separate front panel.  I believe the Micamold transmitter was set up that way.

I've designed a lot of circuit boards and would like to try this.

So.  Any comments?  Objections?  Suggestions?

--73--

--Jeff Duntemann KG7JF
  Scottsdale, Arizona

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

Date: Mon, 4 Nov 1996 14:03:43 -0500 (EST)
From: Paul Bernhardt <[email-masked]>
To: Gordon Gekko <[email-masked]>
Cc: glow bugs <[email-masked]>
Subject: Another 10Y description
Message-ID: <[email-masked]>

Gordon,
  I hope you are not saturated with 10Y descriptions.
  My RCA Transmitting Tube manual (Tech. Manual TT-5) states:
10Y  Power Triode
  Thoriated-tungsten-filament type used as rf power amplifier and 
oscillator.  May be used with full input up to 8 Mc.  Requires small 
four-contact socket and may be mounted in vertial position only, base 
down.  ST-16 Outline.
Filament volts (ad/dc) 7.5.  Filament current 1.25 Amperes.
Direct interelectrode capacitances:
grid to plate 7 uuf; 
grid to filament 4 uuf; 
plate to filament 3 uuf.
Maximum CCS ratings as RF POWER AMPLIFIER AND OSCILLATOR, CLASS C TELEGRAPHY:
DC plate volts, 450 MAX; 
DC grid volts, -200 MAX;
DC plate milliamperes, 60 MAX; 
DC grid milliamperes, 15 MAX;
Plate input, 27 MAX Watts;
Plate Dissipation, 15 MAX Watts.
Plate shows no color when tube is operated at maximum CCS ratings.  The 
10Y is a DISCONTINUED type listed for reference only.  The 801A is a 
direct replacement for the 10Y.

Paul Bernhardt, KF4FOR  

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

Date: Mon, 04 Nov 96 18:18:35 AES
From: [email-masked] (Murray Kelly)
To: [email-masked]
Subject: 6BM8 tubes
Message-ID: <[email-masked]>

>From: [email-masked] (Lee Richey)
>Subject: 6BM8 transmitter and other stuff
>Now I'm planning a little 10-15 watt input crystal rig.  I hav a couple
>6BM8's
>in the junk box.  Does anyone here know how well the 6BM8 works at RF?  
>It was specifically designed for audio I believe.  Most audio tubes work
>just
>fine on RF, but a few do not because of internal lead length etc.  Looks
>like
>it would make a pretty nice little rig.  I'm planning to have pretuned
>pi-net
>output so I can switch bands without putting up a carrier for tune-up.  
>(That's one nice thing the SS rigs have produced, lots less tuners-uppers)
> 
>-73- -Lee- -WA3FIY-

I am also interested in using these tubes since I have a few 'pulls' from
old TVs. Any progress reports would be appreciated here.

Murray Kelly vk4aok

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

Date: Mon, 4 Nov 1996 16:01:05 -0500
From: [email-masked] (Lee Richey)
To: <[email-masked]>
Subject: Re: Printed Circuits that Glow
Message-ID: <[email-masked]>

> Just wanted to take the pulse here: What do y'awll think of tube circuits
on
> PC boards?
 
I think it is fine.  It's the soft glow, the odor of dust and bugs burning
:-), the sense that this thing just sounds better than that solid state
thingy that makes tube rigs more fun to use.

>My vision is
> a circuit board the size of the chassis bottom plate, bolted to the
inverted
> chassis with the traces on the underside to keep B+ out of the way.  The
> bottom plate then becomes the front panel.  Or, with some cleverness, I
> could mount the tuning caps inside the chassis and not bother with a
> separate front panel.  I believe the Micamold transmitter was set up that
way.

This is almost exactly how I am doing the 6BM8 TX.  I am using double
sided unetched pc board material in the prototype.  It makes a great
ground plane and is relatively easy to work with.  Your other point,
keeping
the B+ out of the way, is no small issue, especially if the item becomes a
kit.  Not too many of the newer hams have worked with high voltages and
legal liability is an issue as well.  The resulting design must be safe.

-Lee-  -WA3FIY-

http://www.radioadv.com

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

Date: Mon, 4 Nov 1996 13:53:33 +0000
From: "Brian Carling" <[email-masked]>
To: [email-masked]
Subject: Re: Printed Circuits that Glow
Message-ID: <[email-masked]>

HEY! It's a reply from AF4K!
On  4 Nov 96, Jeff Duntemann wrote:

> Hi gang--
> 
> Just wanted to take the pulse here: What do y'awll think of tube
> circuits on PC boards?

Jeff - the big problem I have seen with that is in the 
implementation.

If it is done right, there may be no problem, but I have worked on 
MANY pieces of equipment that the designers sought to marry 
tube technology with PC boards, and the usual problem was the 
mechanical strain exerted by HEAVY components on circuit borads that 
have delicate copper traces attached to them. The resultant flexing 
from the heavy parts is what will cause a problem, because those 
delicate traces get cracked or torn easily. They are essentially 
almost as weak as paper! The copper plating should be VERY thick
if one is to succeed, and parts positioned so that tube sockets 
cannot rip away from their connections to the PC board.
If I was going to do that (and I have considered it lately) - I would 
factor into the design, a means of restraint for the heavier caps, 
tubes and other pieces. 

Axial lead capacitors are not good to use in high-vibration 
environments to begin with, and I can't imagine putting tose long, 
heavy radial lead caps on a PC board either. I'd mount them somewhere 
else, firmly secured to the chassis some way, either with FP mounting 
or with the black plastic clips.

Happy building!
********************************************************
*** 73 from Radio AF4K / G3XLQ in Gaithersburg, MD USA *
**  E-mail to:  [email-masked]                         *
*** See the great ham radio resources at:              *
**  http://www.mnsinc.com/bry/                         *
********************************************************

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

Date: Tue, 5 Nov 1996 13:22:18 +1000
From: [email-masked] (Peter Holtham)
To: [email-masked]
Subject: Re Glowbugs admin ... please read
Message-ID: <v01540b01aea45dd476c9@[130.102.44.39]>

In response to an earlier post, I am just one of the lurkers on the
Glowbugs net, reading all the posts with interest. Keep up the good work.

I have just been leafing through the latest edition of the 1996 catalogue
of RS Components. RS are an Australian offshoot of the British company
Radiospares (I think they also trade as RS components). The catalogue is
very big with lots of new ics and other bits and pieces every few months,
the latest and greatest in silicon etc etc. Right in the middle of the
semiconductors section is a NEW LINE - thermionic valves (tubes). They can
supply 12AT7, KT88, 6L6GC and about 10 other types, some have been
'specially tested' to meet the needs of 'audiophiles'. What the testing
involves is not stated although it does involve an oscilloscope. The same
outfit also supplies chassis punches in a range of size that someone was
looking for recently. I don't know whether they have a US offshoot, but
suspect not. You can't keep those glowbugs down!

73,

Peter VK4COZ

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

Date: Mon, 4 Nov 1996 22:01:48 -0700 (MST)
From: "James P. Rybak" <[email-masked]>
To: Glowbugs <[email-masked]>
Subject: "The Ocean Hopper" Magazine
Message-ID: <[email-masked]>

Several years ago, Bill Albrant published "The Ocean Hopper" magazine.  
Copies are no longer available from Bill.

I would like to borrow and photocopy the issues of that magazine from 
anyone who has them.  I will take VERY GOOD care of them and return them 
promptly after photocopying.  I also will pay postage costs both ways and 
provide any other incentive an owner of these magazines might request.

Thanks.

Jim Rybak  W0KSD

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

Date: Mon, 4 Nov 1996 22:44:56 -0700
From: "Deane D McIntyre"  <[email-masked]>
To: [email-masked]
Subject: Reprint of '29 and '34 Handbook chapters
Message-ID: <[email-masked]>

Gang:

Got my 1997 Antique Electronic Supply Catalog (postmarked Amsterdam,
the Netherlands for some strange reason) in the mail today. One
new item that caught my eye as being of interest to Glowbuggers
is the following book:

Those Great Old Handbook Receivers. Chapters from the 1929 amd 1934
ARRL Radio Amateur's Handbook.

"Chapters deal with detailed receiver theory, construction techniques
and power supply secrets from the 1929 and 1934 editions of ARRL Handbook"

158 pages. 0.8 lb. B-741.....$8.95

I have never heard of this book, but it sure sounds interesting
for people like me without pre-war Handbooks and QST's. Must
be a few good regen circuits I would think using UY-227's and other
"new" tubes....too bad they don't include the transmitter chapters
as well.

Incidently in the catalog 6T9's are still $2.30 but 45's are now
$80.00 new, $37.50 for used ST and $67.50 for used globe type.
50's are $140.00 for used, call for new......the new 12L6GT's at
$1.60 are closer to my price range me thinks for glowbugging.....

I have no correction with AES (except as a customer...)

73, Deane D McIntyre VE6BPO
[email-masked]

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

Date: Tue, 5 Nov 1996 06:48:57 -0800
From: [email-masked] (michael silva)
To: [email-masked]
Subject: Re: Reprint of '29 and '34 Handbook chapters
Message-ID: <[email-masked]>

>Those Great Old Handbook Receivers. Chapters from the 1929 amd 1934
>ARRL Radio Amateur's Handbook.

>I have never heard of this book, but it sure sounds interesting
>for people like me without pre-war Handbooks and QST's. Must
>be a few good regen circuits I would think using UY-227's and other
>"new" tubes....

I picked up this book a few months ago from Lindsay.  It's definitely 
good reading, with both regens and superhets.

>Incidently in the catalog 6T9's are still $2.30 but 45's are now
>$80.00 new, $37.50 for used ST and $67.50 for used globe type.
>50's are $140.00 for used, call for new......the new 12L6GT's at
>$1.60 are closer to my price range me thinks for glowbugging.....

The 12L6 holds a special place (!?) in my personal glowbug revival.  
Soon after I got my first AES catalog I saw them and noticed how cheap 
they were.  Well, figures I, 6L6s may cost a bunch, but I can buy some 
real cheap 12L6s and a 12v filament transformer and be way ahead of the 
game, so that's what I did.  Boy was I surprised when they showed up!  
To those of you who don't know the punchline, the 12L6 is *not* a 12v 
6L6, but a 10 watt output tube in the 25L6/50L6 family.  It's 6v 
equivalent is actually the 6W6/6DG6.  And I thought I was being so 
clever...

73,
Mike, KK6GM

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

End of GLOWBUGS Digest 342
**************************