Subject: GLOWBUGS digest 428

From: [email-masked]
Date: Mon, 27 Jan 1997 18:35:27 GMT

GLOWBUGS Digest 428

Topics covered in this issue include:

  1) Subminiature tube receiver
	by Chris <[email-masked]>
  2) Need VTVM Manual
	by Bob Marsh <[email-masked]>
  3) SB-301/401 - On The Air
	by Bob Marsh <[email-masked]>
  4) Re: What tube would you use in a lifetime application?
	by [email-masked]
  5) Re: What tube would you use in a lifetime application?
	by [email-masked]

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Date: Sun, 26 Jan 97 16:18:59    
From: Chris <[email-masked]>
To: [email-masked]
Subject: Subminiature tube receiver
Message-ID: <[email-masked]>

Hi Folks,
  Several people showed interest in the PC board tube receiver so I stuck a few photos 
of it on my WEB page. If you would like to have a look go to:

   www.conknet.com/piexx

and follow to PIEXX and then to new products, its at the bottom of that page. Or:

   http://www.conknet.com/piexx/piexx/new/new.htm

Thanks,
-Chris

-------------------------------------
Name: Chris
E-mail: Chris <[email-masked]>
URL http://www.conknet.com/piexx
Date: 1/26/97
Time: 4:18:59 PM

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

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Date: Sun, 26 Jan 1997 20:22:05 -0500
From: Bob Marsh <[email-masked]>
To: Glowbugs List Server <[email-masked]>,
Subject: Need VTVM Manual
Message-ID: <[email-masked]>

Hi everyone,

I just got an RCA Senior Volt Ohmist mod WV98A.  I'm looking for a
manual or copy with the maintenance/calibration procedures.  I'll be
happy to reimburse, etc, etc.

Thanks

Bob/KB2SGM

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Date: Sun, 26 Jan 1997 20:31:52 -0500
From: Bob Marsh <[email-masked]>
To: Glowbugs List Server <[email-masked]>,
Subject: SB-301/401 - On The Air
Message-ID: <[email-masked]>

Hi all,

I finally got the Heath "Twins" finished and on the air.  Reports on the
signal have been very good. (guess I finally managed to do something
right!)

I still have to do another alignment (I get better at it each time i do
it) and probably replace the finals at some point.  I'm getting between
50 and 65 watts out depending on the band/freq on CW, but I'm pretty
sure another alignment will help some.

For now, though, I'm just gonna play with it a while!  I'm really
impressed with the receiver - it sounds great!  All my solid state gear
is collecting dust over here from lack of use.

Thanks to all who provided advice and encouragement.  That glimmer of
understanding is getting a little brighter!

73 de Bob/KB2SGM

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Date: Mon, 27 Jan 1997 12:03:50 -0500 (EST)
From: [email-masked]
To: [email-masked]
Cc: [email-masked] (), [email-masked]
Subject: Re: What tube would you use in a lifetime application?
Message-ID: <[email-masked]>

> > 1)  ONE tube type used throughout, for spares conservancy.
> 
> All things considered, I would pick the most common pentode available
> today which would perform well at the RF frequencies. If a tube works well
> at RF, it will work well at IF/audio frequencies. In my mind, the
> noise figure and cutoff characteristics, would be important.

This is a good point.

After reading this, I would probably approach it somewhat like this.....

1) pick a common triode type.  (thinking of regenerator service here)

2) pick a common pentode type.  (this is where the generic doall tube
                                 would be of value)

> As someone else said, you can always wire a pentode as a triode and
> can always parallel them for power capability. It is probably not a good
> idea to use triodes in IF and RF amps because of the tendency for them
> to oscillate. 

For the sake of generic glowbugging, I would still opt for a generic
triode and a generic pentode, then, for utility.  There are some
instances where triodes are just easier to play with, and many instances
where pentodes are more stable, so the case for 1 type of each is
probably valid.

> For HF, I guess I'd choose something like the 6AU6, 6BA6, or 6CB6 
> (whichever is remote cutoff for good AGC use). i

Well, there are a buku's gazillion different types.  The problem is
which one is likely to be around in sufficient quantity to be a
workable glowbugging device for the next X number of years.

Is there one type that particularly would shine, in terms of generic
subbability and good cutoff/AGC action/transconductance, etc?

Is there a common sleeper variety that is not a sought after type
as used in the Hamarcollijohnsiscratchers, etc?

> > There are many ways to approach the problem, and back when I was a pencil
> > pocket protector geek kid, I would have taken one approach.
> 
> NOW WATCH IT! I still use a pocket protector!

Gee, there are still a few of us around...... Are you still wearing the
classic white shirt with narrow string tie and still carrrying the
leather softeside satchel?.........(:+}}.....

There is something to be said for the carrying capacity of that softside
satchel brief case...... but string ties...... nah, not since I let me
hair grow down in the 60's and sported the Tijuana retreads and beads
.... (:+}}.....

73/ZUT DE NA4G/Bob UP

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Date: Mon, 27 Jan 1997 12:06:36 -0500 (EST)
From: [email-masked]
To: [email-masked]
Cc: [email-masked] (), [email-masked]
Subject: Re: What tube would you use in a lifetime application?
Message-ID: <[email-masked]>

> > What Tube Would You Use in a Lifetime Application for a Receiver
> > That Would be Based Upon ONE Tube Type Throughout:
> > ****************************************************************
> > Well, Bob, without much thought I'd think about the 6SN7.  Nice
> > double triode, versatile, and 4.3 quadzillion of 'em were made
> > during the glowing TV era.
> 
> I have an old Flying Doctor rig here that uses exactly that tube
> right thru. One didn't want to have to keep a bunch of different
> valves in the cupboard in case sumpin' went wrong. And anyhow,
> since you didn't know which tube was bung, you switched them round
> till it worked again!

Well, Murray, that is exactly the reason why I pose this thread,
because there may come a time when the really odd tubes are not
commonly found, and a generic sub for play will have to be worked out.
The Flying Doctor rig would be a classic example of that utility.

Tell us a bit more of that rig, for discussion.....

Bob/NA4G

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End of GLOWBUGS Digest 428
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