Subject: GLOWBUGS digest 335

From: [email-masked]
Date: Tue, 29 Oct 1996 10:13:35 -0600 (CST)

GLOWBUGS Digest 335

Topics covered in this issue include:

  1) Re: TUBE BANK(s) Idea!
	by [email-masked] (Larry Szendrei, NSME CMOS7 BEOL integration)
  2) Re: Homebrew UX-201A regen grid leak value?
	by HaPpYgUy <[email-masked]>
  3) Night Deposit at the All-Night Tube Bank?
	by [email-masked] (Jeff Duntemann)
  4) Re: Lurker Needs Knight T-60 Ckt.
	by Roy Morgan <[email-masked]>
  5) Re: emergency output transformer
	by Roy Morgan <[email-masked]>
  6) Looking for hole punches
	by Guy Dragoo <[email-masked]>
  7) 
	by Roy Morgan <[email-masked]>
  8) Chassis concepts
	by [email-masked] (Jeff Duntemann)
  9) Re: Looking for hole punches
	by [email-masked] (Jeff Duntemann)
 10) Tube Bank
	by [email-masked]
 11) Re: Tube Bank
	by "Robert M. Bratcher Jr." <[email-masked]>
 12) Re: Tube Bank
	by Gordon Gekko <[email-masked]>
 13) Re: TUBE BANK(s) Idea!
	by [email-masked] (Richard H. Arland)
 14) Tube bank
	by [email-masked] (Jim Haynes)
 15) Re: Lurker Needs Knight T-60 Ckt.
	by "Brian Carling" <[email-masked]>
 16) Re: Tube bank
	by "Brian Carling" <[email-masked]>
 17) Re: Tube Bank
	by "Brian Carling" <[email-masked]>
 18) Re: Fr. Roy
	by [email-masked] (Richard H. Arland)
 19) Online Schematics
	by Gordon Gekko <[email-masked]>
 20) Tube Bank EXISTS!!
	by [email-masked]
 21) re: Tube bank
	by [email-masked]
 22) Pinouts on type 30 tubes?
	by Art Winterbauer <[email-masked]>
 23) Re: Chassis concepts
	by [email-masked] (Jeff Duntemann)
 24) Electric Radio Magazine
	by [email-masked] (Jeff Duntemann)

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

Date: Mon, 28 Oct 1996 12:22:06 -0500
From: [email-masked] (Larry Szendrei, NSME CMOS7 BEOL integration)
To: [email-masked], [email-masked]
Subject: Re: TUBE BANK(s) Idea!
Message-ID: <[email-masked]>

>My idea is that for the first year, you would take them on the basis
>that someone would have to donate two tubes for every ONE tube they 
>withdrew. That would help build up the stocks etc.

Sure!!! I'll give you FOUR 6U8's for TWO type 50's! :-)

Seriously, tho, it IS a great idea.

73,
Larry

Larry Szendrei, ARS NE1S
[email-masked]
(not a list member, but read the archives religiously, and of the same ilk as 
the glowbuggites!)

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

Date: Mon, 28 Oct 1996 13:30:39 -0800 (PST)
From: HaPpYgUy <[email-masked]>
To: [email-masked]
Cc: Multiple recipients of list <[email-masked]>
Subject: Re: Homebrew UX-201A regen grid leak value?
Message-ID: <[email-masked]>

On Mon, 28 Oct 1996 09:25:04 -0600 (CST) [email-masked] 
wrote:
>...But, they
> should be run in general detector service at the LOWEST voltage possible
> consistent with good gain and smooth regeneration.  On my set, that value
> can be anywhere from about 3.75 volts up to about 4.5 volts, usually best
> at right around 4.0 volts on the detector filament and first audio filament.

Looking at an old RCA tube manual, it rates the filament voltage of the UX-201a as 
5 volts +/- 10%. This means that the tube should be operated within 4.5 to 5.5 volts.
This is true for these tungsten filaments that need to maintain a molecular layer of 
thorium on the filament surface to operate correctly. If burned too brightly, the 
filament burns off this thorium too quickly, reducing emmissions. On the other 
hand, if it burns at too low of a temperature, the thorium builds up too rapidly on the 
filament, reducing emmissions. It is true that the tube characteristics become 
extremely non-linear at reduced filament voltages resulting in apparently better 
detection but you will ruin these 70 year old tubes before their time! A fix to 
'restore' these tubes to former emmissions is to 'flash' them, that is, to apply only 
filament voltage of about 8 or so volts for a couple of minutes, and then 5 volts for 
about 12 hours WITHOUT plate voltages of any kind, if used in the manner 
suggested by a fellow glowbuggite. This will restore the layer of thorium onto the 
filament surface surface again bringing up emmissions. Kinda hard on a tube too, 
because it could potentially burn out the filament once and for all, or at best 
reduces it's 10,000 hr. filament life substantially even tho' the tube is restored 
again.
I suggest a proper circuit for these triodes having the gridleak not across the grid 
condenser, but from the grid to the filament pin with the POSITIVE filament voltage, 
unless of course the grid circuit followed through the coil and tuning capacitor(s) 
goes there anyway. By biasing these tubes in this manner, nonlinearity is 
introduced, which assists detection greatly. In this way, proper filament voltages 
are maintained, leading to increased tube life without flashing or weak emissions.  
Another option for those wanting to play with filament voltages is to get a REAL 
tungsten filament tube, such as the UV-201 or UX-201 (without the a). This one 
burns like a lightbulb at 5 watts (5 volts, 1 ampere). With this tube you can play 
around with the filament voltages without harmful effects up to the rated voltage. 
Some of the earliest regen sets were built for this tube and actually varied the 
filament voltage to gain some volume or regen control.
Another option is to use a soft detector tube designed especially for regenerative 
sets. These tubes have been designed gasseous for intentional nonlinearity at 
their rated voltages. A good example are the UV200/UX200/UV200a/UX200a. In the 
case of these detector tubes, the gridleak resistor must return to the NEGATIVE 
side of the filament, as in a conventional amplifier. the UV200a operates well from 
between 22.5 to 45 volts. If connected in this correct manner, the 200a is a better 
detector than a 201a , although it's input impedance is somewhat less than a 201a. 
Nothing that proper tuning can't fix tho' ..

In a nutshell: Use the right tube at the right voltages or substantially reduce the life 
of your 70 year old tubes.       

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

Date: Mon, 28 Oct 1996 12:53:26 -0700
From: [email-masked] (Jeff Duntemann)
To: [email-masked]
Subject: Night Deposit at the All-Night Tube Bank?
Message-ID: <[email-masked]>

I actually have a box of tubes all packed up with nowhere to go, has been
for several years now.  To save space I pulled all the old 1X2-style
rectifier tubes I had in stock from old TVs, plus other tubes out of TVs
that seemed without amateur application.  I hate to just dump them but only
a few are NOS, the rest pulls, and it's unclear what to do with them. Free 
to a good home.  I'll even pay the shipping.  Anybody got any ideas?

--73----Jeff Duntemann KG7JF
  Scottsdale, Arizona

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

Date: Mon, 28 Oct 1996 15:04:44 -0500
From: Roy Morgan <[email-masked]>
To: [email-masked]
Subject: Re: Lurker Needs Knight T-60 Ckt.
Message-ID: <[email-masked]>

At 05:55 PM 10/27/96 -0600, you wrote: 

..   more recently, 
>a solid state QRP transceiver ( sorry for the 2 counts of blasphemy )...
>that produced a few thrills of it's own !!
>
>Now, in atonement, I'm starting to rebuild a Knight T-60 transmitter.

You are forgiven of all you sins.  

In further atonement, you will keep the group posted as to your progress,
accept all offers of parts, information, and advice, and put the thing on
the air whenever you get around to it.

Go in peace.
 
(and whatever you do, Keep em glowing!)

-- Roy Morgan/Building 820, Room 562/Gaithersburg  MD 20899
(National Institute of Standards and Technology,  formerly NBS)
301-975-3254 Fax: 301-948-6213  [email-masked] --

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

Date: Mon, 28 Oct 1996 15:23:25 -0500
From: Roy Morgan <[email-masked]>
To: [email-masked]
Subject: Re: emergency output transformer
Message-ID: <[email-masked]>

At 12:29 AM 10/27/96 -0500, you wrote:
>
>While trying to get some sound out of the old HRO I obtained today,
>I was in need of an audio output transformer. 
..
>
>I ended up using a Stancor 24 watt line to voice coil unit.

Bob gets my vote for the glowbuggers spirit of the day award!

Keep em glowing!

-- Roy Morgan/Building 820, Room 562/Gaithersburg  MD 20899
(National Institute of Standards and Technology,  formerly NBS)
301-975-3254 Fax: 301-948-6213  [email-masked] --

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

Date: Mon, 28 Oct 1996 14:31:16 -0600
From: Guy Dragoo <[email-masked]>
To: "'Multiple recipients of list (Boatanchors)'"
Subject: Looking for hole punches
Message-ID: <[email-masked]>

I am looking for a set of hole punches from 1/4 to 1 1/in for punching aluminum chassis.  
Does anyone know of a vendor that carries these at a good price (Sescom, which seems to have a pretty good price, still runs over 150 bucks for all the flavors I need).
Any and all suggestions welcome.
Thanks and 73
Guy AC5HL

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

Date: Mon, 28 Oct 1996 15:43:06 -0500
From: Roy Morgan <[email-masked]>
To: [email-masked]
Message-ID: <[email-masked]>

At 05:55 PM 10/27/96 -0600, you wrote: 

.   more recently, 
>a solid state QRP transceiver ( sorry for the 2 counts of blasphemy )...
>that produced a few thrills of it's own !!
>
>Now, in atonement, I'm starting to rebuild a Knight T-60 transmitter.

You are forgiven of all you sins.  

In further atonement, you will keep the group posted as to your progress,
accept all offers of parts, information, and advice, and put the thing on
the air whenever you get around to it.

Go in peace.
 
(and whatever you do, Keep em glowing!) 

-- Roy Morgan/Building 820, Room 562/Gaithersburg  MD 20899
(National Institute of Standards and Technology,  formerly NBS)
301-975-3254 Fax: 301-948-6213  [email-masked] --

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

Date: Mon, 28 Oct 1996 13:55:33 -0700
From: [email-masked] (Jeff Duntemann)
To: [email-masked]
Subject: Chassis concepts
Message-ID: <[email-masked]>

Hi gang--

I got down to some serious chassis work on my 6U8 superhet this weekend, and
it occurred to me the general approach I use might be new to some people,
tho I can hardly claim to have invented it.  Wish I had better facilities to
deliver images.  With some luck I'll have my Junkbox Radio page up on the
Web before the end of the year.  One picture would make the whole thing as
obvious as a popped electrolytic.

But the idea is this: I take a typical aluminum chassis such that one can
buy from AES, along with a matching bottom plate, either boughten or hacked
up from sheet stock.  The chassis I invert, and use the bottom plate as the
main platform for construction.  That is, the tubes, the IF cans, and so on,
are mounted to the bottom plate.  This makes the receiver MUCH easier to
wire, as I'm not "digging down into the well" so much, as I would be if I
were wiring parts underneath a chassis in the traditional fashion.

But it gets better.  I hack up a front panel out of more sheet stock, and
bolt it to the chassis bottom plate with 1" X 1" aluminum angle like you see
at the hardware superstores.  For smaller assemblies I've used Erector Set
angle girders, which are nickel-plated steel and punched with accurate holes
every 1/2".  You can sometimes pick up modern Erector Sets (not the ancient
Gilbert sets, which are now collectibles) at garage sales for a few bucks,
and the girders and brackets can be *very* useful in chassis work.

You now have a front panel bolted to the horizontal plate where the bottles
and cans actually live.  One more step: You remove the front face from the
upside-down chassis.  Three cuts with a saber saw did it for me, plus a
little file work to even out the edges.  Leave yourself at least 3/8" on
each side to give you a flange into which to sink a couple of sheet metal
screws.  The front panel/horizontal plate assembly can now be bolted neatly
to the upside-down chassis, giving a very rigid unit with an RF-tight
compartment inside the chassis.

Virtually all the wiring can be done on the plate-and-panel assembly,
leaving nothing but the fuse holder, power cord, and SO-238 on the chassis
itself.  I put a 1 3/4" steel spacer on the back edge of the horizontal
plate to act as a "foot" to keep the working assembly more-or-less
horizontal when it's not bolted to the chassis box.

I got as far as mounting the Velvet Vernier mechanism and the RF amp tuning
cap before I ran out of weekend.  There aren't a lot of controls and I
should be able to get the rest of them mounted this week.

My only regret on this project is that I didn't go to the next larger
chassis size.  But isn't that always the case?

--73--

--Jeff Duntemann KG7JF
  Scottsdale, Arizona

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

Date: Mon, 28 Oct 1996 14:04:20 -0700
From: [email-masked] (Jeff Duntemann)
To: [email-masked]
Cc: [email-masked]
Subject: Re: Looking for hole punches
Message-ID: <[email-masked]>

At 02:32 PM 10/28/96 -0600, AC5HL wrote:
>I am looking for a set of hole punches from 1/4 to 1 1/in for punching
aluminum chassis.  
>Does anyone know of a vendor that carries these at a good price (Sescom,
which seems to have a pretty good price, still runs over 150 bucks for all
the flavors I need).

Punches are never cheap, and the square ones are purely hopeless.  I see 1
1/8" round hole punches at flea markets regularly; they're apparently a
standard electrical conduit size but work well for most octal tube sockets.
Big hardware stores carry them new.

The only consolation in paying the going price is remembering how much work
it was to drill a ring of 1/16" holes with a hand drill and then filing
between the holes with a needle file to knock the slug out--THEN cleaning up
the ragged hole with a rat tail or half-round file.  Eeee-yukh!

Philmore makes (or made) a set of small circular metric punches that was
only $35.  I bought it from Halted Specialties in Santa Clara about ten
years ago, when I lived in Scotts Valley.  The metric sizes were close
enough to English in many cases that I don't sweat the delta, and you
couldn't beat the price.  Don't know where one would find that set today.

You mentioned Sescom; I have a catalog from Project Pro that lists some
gorgeous chassis and panels, ostensibly for tube audio but very appropriate
for high-end RF work as well.  Same sort of place.  I keep wanting to call
them and make sure they're still in business.  You never know with
glowbug-friendly vendors...

--73--

--JD--

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

Date: Mon, 28 Oct 1996 14:05:53 -0800
From: [email-masked]
To: [email-masked]
Subject: Tube Bank
Message-ID: <[email-masked]>

I posted a message a few days ago about starting a tube bank but have not 
seen any responses. Perhaps I might elaborate a little as it might be a good 
idea. I ran a bank for Air Force MARS a while back.
These are some thoughts:
  1. The Bank would be operated on a STRICTLY non profit basis. This means            
volunteer.
  2. Operations would be restricted to the GLOBUGS and BOATANCHORS lists and 
would be for the benefit of those who use these lists.
  3. The Bank would solicit donations as appropriate via these two lists.
  4. Users would send requests to the bank stating the specific project the 
tubes would be used in. 
  5. Tubes would be supplied on an availability only basis from stock, the 
only charge being for packing and shipping. Another possibility is a two for 
one type of swap which may have some merit but would be difficult to 
administer. 

The principal trap in this idea is that it is wide open for abuse. For 
example tubes being solicited from the Bank and then resold at a profit. 
However, as it is highly unlikely that The Bank would ever have such things 
as WD-11s or 6L6s or anything of serious value this is probably not a risk 
to be concerned with.

This is just an idea so kick it around Guys and Gals.
Dave KI6QE/7

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

Date: Mon, 28 Oct 1996 17:05:24 -0600
From: "Robert M. Bratcher Jr." <[email-masked]>
To: [email-masked]
Subject: Re: Tube Bank
Message-ID: <[email-masked]>

At 10:06 PM 10/28/96 +0000, you wrote:
>I posted a message a few days ago about starting a tube bank but have not 
>seen any responses. Perhaps I might elaborate a little as it might be a good 
>idea. I ran a bank for Air Force MARS a while back.
>These are some thoughts:

>The principal trap in this idea is that it is wide open for abuse. For 
>example tubes being solicited from the Bank and then resold at a profit. 
>However, as it is highly unlikely that The Bank would ever have such things 
>as WD-11s or 6L6s or anything of serious value this is probably not a risk 
>to be concerned with.
>
>This is just an idea so kick it around Guys and Gals.
>Dave KI6QE/7

I have a small stock of tubes myself including a nice pair of glass 6L6G's
that I intend to keep along with a new looking pair of 807W's that I've had
over 15 years. Generally when I buy a box of tubes at my local antique radio
club or a swap meet, what I want from it gets pulled out then the box gets
sold 2 or 3 months later at another meet for whatever I can get. Never made
a profit on any of this. I've got plenty I'm not using for such a tube bank
if we ever start one. 

Or better yet, Why don't members just ask on the list for any tubes they
need? Whoever has the tubes could send them direct! The"profit minded"
members problem wouldn't be with us. That way we don't need a central bank.
Everyone just asks (or trades)for what they need.

Robert M. Bratcher Jr.
E-mail to:
[email-masked]
Record collector, 8mm, super 8, 16 and 35mm Film collector.
I like old radio's too.
Collins, Hallicrafters, National & Hammurland are my Favorites!

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

Date: Mon, 28 Oct 1996 15:30:34 -0800 (PST)
From: Gordon Gekko <[email-masked]>
To: [email-masked]
Subject: Re: Tube Bank
Message-ID: <[email-masked]>

Robert M. Bratcher Jr." <[email-masked] said:

>Or better yet, Why don't members just ask on the list for any tubes they
>need? Whoever has the tubes could send them direct! The"profit minded"
>members problem wouldn't be with us. That way we don't need a central bank.
>Everyone just asks (or trades)for what they need.
>

My vote is for the above method of administering the tube bank.  This just
seems the most logical approach - I have a box of tubes that I probably
wouldn't want to send ALL of to the bank, but if a request comes down the pike
to the group at large, I'd be more likely to dig into the box and send one 
off.  to me, that just seems more logical.  The bank in effect becomes all
of us, and no one individual has the hassles and responsibilities of
administering 
it.  Looked at that way, the 'bank' already exists and has a HUGE inventory!

Just my 2 cents worth.

73's

Dave
aka [email-masked]

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

Date: Mon, 28 Oct 1996 22:14:07 PST
From: [email-masked] (Richard H. Arland)
To: [email-masked], [email-masked]
Cc: [email-masked], [email-masked]
Subject: Re: TUBE BANK(s) Idea!
Message-ID: <[email-masked]>

I have been going thru my stock of tubes here and have pulled out a dozen
12AX7, 12AU6, 12BE6, 6AU6 etc. Checked them all out and so far, all check
good (using a Eico Mdl 657 transconductance dynamic tube checker). 

I'll donate half (that is 6 each) of the above mentioned tubes along with
others that I get a chance to check out to start things off. These are
all good tubes. I am after some 6C4s, 6BE6s, 6BA6s 6CB6s & 6BZ6s in
particular to throw into the kitty. I have over 5 boxes of tubes left to
go thru. Also found some 35W4s, 50C5s, 12AU7s, etc that came out of the
"All American 5 tube receivers" and have multiple quantities of all of
these tubes. Will split them with the tube bank. 

The station whre I work part time has a big basement full of old
tubes....some type 50s, 80s etc along with some metal 6SK7s etc. Will
get permission to remove these, test same and donate them, as time
permits.

I only wish I had the time to do the tube bank from here. I work two jobs
in addition to writing for the radio hobby press, so time is nonexistant
for me. (as my wife continually points out when she sees the two Heath
transceivers laying on their respective backs waiting to be fixed, one
VCR, two CB sets etc.)

73 rich K7YHA

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

Date: Mon, 28 Oct 1996 18:22:47 -0800
From: [email-masked] (Jim Haynes)
To: [email-masked]
Subject: Tube bank
Message-ID: <[email-masked]>

I'm in support of the suggestion that you just keep your tubes and ask
on the list when you need one.  We need one addition - that if you can't
keep your tubes then offer to send them to someone who can.  They must
never go to the dump, since there aren't any more being made.

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

Date: Mon, 28 Oct 1996 20:07:58 +0000
From: "Brian Carling" <[email-masked]>
To: Roy Morgan <[email-masked]>, [email-masked]
Subject: Re: Lurker Needs Knight T-60 Ckt.
Message-ID: <[email-masked]>

HEY! It's a reply from AF4K!

Roy (& the group):

This reads like it must be the ENTIRE FAQ for glowbugs!
At least, that could be the answer to all FAQs!

72.5 - Bry, G3XLQ

On 28 Oct 96, Roy Morgan wrote:

> At 05:55 PM 10/27/96 -0600, you wrote: 
> 
> ..   more recently, 
> >a solid state QRP transceiver ( sorry for the 2 counts of blasphemy
> >)... that produced a few thrills of it's own !!
> >
> >Now, in atonement, I'm starting to rebuild a Knight T-60
> >transmitter.
> 
> You are forgiven of all you sins.  
> 
> In further atonement, you will keep the group posted as to your
> progress, accept all offers of parts, information, and advice, and
> put the thing on the air whenever you get around to it.
> 
> Go in peace.
> 
> (and whatever you do, Keep em glowing!)
> 
> -- Roy Morgan/Building 820, Room 562/Gaithersburg  MD 20899
> (National Institute of Standards and Technology,  formerly NBS)
> 301-975-3254 Fax: 301-948-6213  [email-masked] --
> 
> 
73 from Radio AF4K / G3XLQ in Gaithersburg, MD USA
[email-masked]
*** See the great ham radio resources at: 
http://www.mnsinc.com/bry/

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

Date: Mon, 28 Oct 1996 20:07:59 +0000
From: "Brian Carling" <[email-masked]>
To: [email-masked]
Subject: Re: Tube bank
Message-ID: <[email-masked]>

HEY! It's a reply from AF4K!
On 28 Oct 96, Jim Haynes wrote:

> I'm in support of the suggestion that you just keep your tubes and
> ask on the list when you need one.  We need one addition - that if
> you can't keep your tubes then offer to send them to someone who
> can.  They must never go to the dump, since there aren't any more
> being made.

GLAD you remembered that very important addendum!

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

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

Date: Mon, 28 Oct 1996 20:07:59 +0000
From: "Brian Carling" <[email-masked]>
To: [email-masked]
Subject: Re: Tube Bank
Message-ID: <[email-masked]>

HEY! It's a reply from AF4K!
On 28 Oct 96, Gordon Gekko wrote:

> Robert M. Bratcher Jr." <[email-masked] said:
> 
> >Or better yet, Why don't members just ask on the list for any tubes
> >they need? Whoever has the tubes could send them direct! The"profit
> >minded" members problem wouldn't be with us. That way we don't need
> >a central bank. Everyone just asks (or trades)for what they need.

> My vote is for the above method of administering the tube bank. 
> This just seems the most logical approach - I have a box of tubes
> that I probably wouldn't want to send ALL of to the bank, 
[snip!]
>  Looked at that way, the 'bank' already exists and has a HUGE
> inventory!

Dave & Bob - it looks like your idea is gathering momentum. It makes 
a heck of a lot of sense. I remember when hams used to help each 
other like this a lot. At one time, you only had to get on a local 2m 
FM repeater and announce that you need a pair of 807s and by that
evening you would have two of them for free. Times are changing but 
not entirely. The spirit of amateur radio lives on!

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

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

Date: Mon, 28 Oct 1996 22:45:59 PST
From: [email-masked] (Richard H. Arland)
To: [email-masked]
Cc: [email-masked]
Subject: Re: Fr. Roy
Message-ID: <[email-masked]>

On Mon, 28 Oct 1996 14:45:19 -0600 (CST) Roy Morgan
<[email-masked]> writes:
> 
>
>At 05:55 PM 10/27/96 -0600, you wrote: 
>
>.more recently, 

>You are forgiven of all you sins.  
>
>In further atonement, you will keep the group posted as to your 
>progress, accept all offers of parts, information, and advice, and put
the thing 
>on the air whenever you get around to it.
>
>Go in peace.
> 
>(and whatever you do, Keep em glowing!) 

Thank you Father Roy, for your words of encouragement and absolution!

73 rich K7YHA

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

Date: Mon, 28 Oct 1996 20:38:30 -0800 (PST)
From: Gordon Gekko <[email-masked]>
To: [email-masked]
Subject: Online Schematics
Message-ID: <[email-masked]>

Ok!  We're ready to roll here.  I have just finished going through the 8 or
so schematics I was sent last week and the week before for 1 tube and 2 tube
transmitters.  Unfortunately, not all of them will scan with enough resolution
to be useable in this format.  

Here is what I have available to start (only 4 - more to come!)

Current Catalog:

File Name:              Description:

1tpi.jpg                1 tube (6V6) transmitter with PI tank
                          output circuit.  Nice circuit.  I
                          built this one myself last weekend.

2t35.jpg                2 tube transmitter - 6L6 final - 35
                          watts plate input

2tpi.jpg                2 tube transmitter - similar to above
                          but with PI tank output circuit

regen1.jpg              2 stage regen (detector plus audio)
                          1939 vintage

The Goal:

To create a database of schematics of tube type gear from the last 75 years
so that future homebrewers won't have to have a library of 1958 QST's to 
find tube-based projects.  This catalog list will be updated approximately
once per week to the group, provided there is new material to post.  Maybe
someday along the way, I'll put the stuff on my webpage for FTP download.

To request:

Simply email me at [email-masked] and mention 'request schematic' in
subject line
and I will send it off within a day so, depending on my schedule.  Order as
many as
you like within reason, but just make sure you give me a valid email
address.  Nothing
is more bothersome than 10 megabytes of jpeg's being bounced over and over
due to a
bum email address!

Submissions:

I am ACTIVELY PROMOTING submission of printed schematics to be scanned and made 
available to everyone in this group.  Eventually, I will amass a database of
tube
types that may be searched to find uses for oddball tubes you may have.  But it
takes submissions to make it work.  Here are the 'rules' for submitting
schematics:

        MUST be full page (81/2 x 11) or very close to it.  I have tried 
        and tried with smaller images and I just can't hold the detail when
        I convert to a compressed format, such as zip or .jpg.  So please - 
        send a full size copy of your diagram.

        Include entire article if desired.  I will only scan the parts list and
        schematic itself, but I will file the rest if some one has questions.

        PLEASE send drawings of circuits you have designed yourself!  Some
of the
        best gizmos ever built didn't appear in QST.

        If you have a scanner, by all means scan the image and send it to me to 
        archive.  Use .tiff or .bmp as the native scan format, using somewhere 
        around 160 dpi resolution.  Much higher and the file becomes way too
large.
        Much less and the finer details drop out.  Then convert the image to 
        .jpg format to send.  Be sure to 'proof' your image before sending
to make
        sure all of the detail has been kept.

        Mail submissions to:

        Dave Ellison 
        1115 Regents Blvd. #16
        Tacoma, WA  98466

        email: [email-masked]

I am currently going through my old schematics to find suitable material to
scan, so
even if no one sends anything, I'll be putting more up to download.        

I've had alot of positive response to this idea, so start sending schematics
and watch
for them to appear in The List.

73's

Dave
[email-masked]

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

Date: Mon, 28 Oct 1996 21:17:41 -0800
From: [email-masked]
To: [email-masked]
Cc: [email-masked]
Subject: Tube Bank EXISTS!!
Message-ID: <[email-masked]>

Well Guys and Gals thanks to Jack G we can stop this thread. There is an 
existing tube bank which operates in exactly the way I had suggested. Was 
announced in September QST. Only drawback is that it does not seem to be on 
the net but rather on an LL BBS in San Diego (619-279-3921). I just checked 
into that BBS and it is right there with a HUGE inventory. As a newcomer to 
the BBS I was not allowed to download but this should be rectified when they 
check my credentials. The bank is operated by:
                     R.L.Wentworth
                     4804 Huron Ave
                     San Diego CA  92117-6211
Those of you out there who are proposing to either junk your surplus or to 
donate to a worthy cause you might consider this one. The guy is a Ham 
(AF6V) and seems to be encouraged by the ARRL as the list is also on the 
ARRL LL BBS but a little more difficult to find.
I will check in again tomorrow night and download the list.
I have never had much success with the idea of just asking for what I need 
although I must admit I have not tried this recently. The central bank idea 
is much better as you can find out beforehand if it has what you need. This 
needs a pretty dedicated person to operate it of course.
73 de Dave KI6QE/7

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

Date: Tue, 29 Oct 96 09:39:11 +0100
From: [email-masked]
To: [email-masked]
Subject: re: Tube bank
Message-ID: <[email-masked]>

Hello GBers,

> > Robert M. Bratcher Jr." <[email-masked] said:
> > 
> > >Or better yet, Why don't members just ask on the list for any tubes
> > >they need? Whoever has the tubes could send them direct! The"profit
> > >minded" members problem wouldn't be with us. That way we don't need
> > >a central bank. Everyone just asks (or trades)for what they need.
> 
> > My vote is for the above method of administering the tube bank. 
> > This just seems the most logical approach - I have a box of tubes
> > that I probably wouldn't want to send ALL of to the bank, 
> [snip!]
> >  Looked at that way, the 'bank' already exists and has a HUGE
> > inventory!
> 
I completely agree with Robert and I would like to extend the existence of this
distributed bank to The Netherlands. I am willing to offer any of my tubes
to any fellow amateur who needs them. I have a rather small collection of
EC.., EF.., EL.., PC.., PF.., PL.. and all kinds of combinations of these.
They are gathering dust, are a regular piece of conversation when the subject
of "cleaning up the shack" arises.

72 de Dirk, PA3GNR

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

Date: Tue, 29 Oct 1996 08:05:15 -0700 (MST)
From: Art Winterbauer <[email-masked]>
To: glowbugs <[email-masked]>
Subject: Pinouts on type 30 tubes?
Message-ID: <Pine.SUN.3.95.961029080131.19946F-100000@spike>

Does anyone know the pinouts on a type 30 tube?  The bottom of the tube looks
like this:

                  O    O

                  o    o

The big Os show continuity with an ohm-meter, so I figured that's the directly
heated cathode.  But of the lower pins, which is the grid and which the plate?

Incidently, the big Os are also physically bigger diameter pins than the other
two.

I'll shortly be trying to build the Globetrotter from an old Dave Ingram article
in CQ and came across a good deal on these type 30 tubes.  

--Art WA5OES

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

Date: Tue, 29 Oct 1996 08:35:34 -0700
From: [email-masked] (Jeff Duntemann)
To: [email-masked]
Cc: [email-masked]
Subject: Re: Chassis concepts
Message-ID: <[email-masked]>

At 08:07 PM 10/28/96 +0000, you wrote:
>HEY! It's a reply from AF4K!
>Great article on your construction method.
>Do you mount the tubes ghorizontally on sub-panel/brackets inside the 
>chassis? Sounds like they do not go through the bottom plate nor 
>through the chassis main panel.

No, the tubes go through the horizontal plate (it's not the "bottom plate"
because the chassis is used upside-down) in the usual fashion.  The working
assembly looks like this, from a side view, with one "tube" shown:

                  |
          ^       | <-- Front panel
         | |      |
         | |      |
------------------|
                  |
                  |

I'll have some photos on my Web site as soon as possible.

--73--

--Jeff Duntemann KG7JF
  Scottsdale, Arizona

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

Date: Tue, 29 Oct 1996 08:44:45 -0700
From: [email-masked] (Jeff Duntemann)
To: [email-masked]
Subject: Electric Radio Magazine
Message-ID: <[email-masked]>

Hi gang--

I'm a little surprised that I never hear anything about Barry Wiseman's
Electric Radio Magazine here.  He's published a number of original tube
designs for homebrewing in the past two years, and told me he'd publish more
if he had them.  The magazine has published a number of Dave Ishmael
designs, and provides practical technical information for restoring and
operating classis HF tube gear, primarily CW and AM.  About a third of the
magazine carries subscriber ads, all for vintage gear and parts.  Much of my
collection of vintage gear has come through answering those ads.

In short, one of the best-kept secrets of the ham radio world.

ELECTRIC RADIO MAGAZINE
Barry Wiseman N6CSW
14643 County Road G
Cortez CO 81321-9575
970-564-9185
[email-masked]

$28 year (12 issues) second class
$38 first class

--73--

--Jeff Duntemann KG7JF
  Scottsdale, Arizona

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

End of GLOWBUGS Digest 335
**************************