Daily GLOWBUGS
Digest: V1 #29
via AB4EL Web Digests @ SunSITE
Purpose: building and operating vacuum tube-based QRP rigs
Subject: glowbugs V1 #29
glowbugs Sunday, May 11 1997 Volume 01 : Number 029
Date: Sat, 10 May 1997 20:35:14 -0800
From: "Kenneth G. Gordon" <keng@uidaho.edu>
Subject: Old radio...
is an AFX-1399, "Electro" Navy Type "3 in 1" Coupler as shown in
The Electro Importing Co., N.Y., Mfrs. 1918 catalog pages 50 and 51,
so kindly FAXed to me this afternoon by Al Klase N3FRQ of
Flemington, N.J. It is made of "...mahogany, handrubbed, piano finish."
Thanks to all who sent info. Pictures will be mailed to those who
asked for them on Tuesday.
Take care, and 73,
Ken W7EKB
Date: Sun, 11 May 1997 09:32:45 +0100
From: BOB DUCKWORTH <bob@atl.org>
Subject: Re: FT: Knight T-60
Sandy-
I'll raise your T-60 to a Hallicrafters HT-37 and a NOS 4-1000 plus
socket and filament transformer for that nice Challanger. Either one
or the other for Adventurer.
tube-Audiophiles,
Rare WE 377A. RED TOP!
To paraphrase AA4RM (Marty), 'All hell broke loose when I plugged this
into my Bogen PA, after it settled in, the absence of noise was
deafening'. Marty is keeping his. You can own the only other one
I've ever seen for a paltry $275.00 plus shipping. It's NOS too!
Glowbuggers,
Found an old Sparton TRF set at a garage sale.
Chassis, no cabinet.
Has some nice parts like 245's and sockets.
Even has battery eliminator!
Before I hack the $6 wonder to bits, I would like
to know if it is truly debris or something I could
parlay into that Challanger :-) Hacking begins on
May 16th.
Found a couple of curious tubes, PM last.
DR715C by General Electronics Inc. (Note, not GE!)
and a couple of 'Valvo' brand EF86
I really like that, 'Yea, we're running Valvo here'
- -bob
Date: Sun, 11 May 1997 14:25:12 -0400
From: John <johnmb@mindspring.com>
Subject: Question for AN/GR109 ops
For the last couple days I've been messing with the GR109 setup,
and have run into one significant problem that I can't understand.
The transmitter and receiver are able to be run off one
antenna, with a pair of back to back diodes to ground, and the
CW key prividing an AC path to ground thru a cap, for the receiver
during transmit.
The problem is, this doesn't seem to work very well.
The receiver sensitivity is about 4x when operated connected directly
to its own antenna, as compared to the arrangement intended. I've
compared notes with two people who are using this setup, one noting
the same performance I do, while the other noting normal performance.
Nothing like a consensus!
For those of you with a schematic, I've changed the .01 cap,
and increased it's value briefly to .1uF with no effect. I've checked
CR1 and CR2, and neither is shorted. I've replaced C14, the 18pF
cap that couples the antenna to the Rx. None of this made the least
bit of difference. I'm wondering if this is not a problem with my set,
but perhaps a design issue.
Anyone else with a 109, please jump in here anytime!
For the time being, I'm heading back to working on the CE200V
to restore my sanity ... but then.. looking at that 16 wafer rotary switch
gives me the chills!
:-)
73
/John
Date: Sun, 11 May 1997 13:54:38 -0700 (PDT)
From: Ken Gordon <keng@uidaho.edu>
Subject: Re: Question for AN/GR109 ops
On Sun, 11 May 1997, John wrote:
> For the last couple days I've been messing with the GR109 setup,
> and have run into one significant problem that I can't understand.
>
> The transmitter and receiver are able to be run off one
> antenna, with a pair of back to back diodes to ground, and the
> CW key prividing an AC path to ground thru a cap, for the receiver
> during transmit.
>
> The problem is, this doesn't seem to work very well.
>
> The receiver sensitivity is about 4x when operated connected directly
> to its own antenna, as compared to the arrangement intended. I've
> compared notes with two people who are using this setup, one noting
> the same performance I do, while the other noting normal performance.
> Nothing like a consensus!
Hi, John. I am one you talked to about this, and I have (had) the exact
same problem.
>
> For those of you with a schematic, I've changed the .01 cap,
> and increased it's value briefly to .1uF with no effect. I've checked
> CR1 and CR2, and neither is shorted. I've replaced C14, the 18pF
> cap that couples the antenna to the Rx. None of this made the least
> bit of difference. I'm wondering if this is not a problem with my set,
> but perhaps a design issue.
After discussing this with you, I did some more thinking. My schematic
seems to show a different value for the RF choke than is really in my
unit. I am wondering if that is the problem. First, why don't you try
simply removing the tubes from the transmitter, and then check the
sensitivity of the receiver. Then you might un-solder one end of (first)
L-9, checking sensitivity, then (leaving L-9 disconnected) un-solder one
end of L-7. Both RF chokes are pretty easy to get to. As I told you in
one of our e-mail exchanges, the HW-16 uses nearly the exact same method
of antenna switching and it works just fine.
73, Ken W7EKB
Date: Sun, 11 May 1997 16:57:19 -0700
From: Bob Rolfness <rsrolfne@atnet.net>
Subject: FS: BC-610 Transformer
Greetings All -
For sale a Stancor Power Transformer out of a BC610, up to model E or
where they changed to a potted version.
$40 plus shipping from 98837 zip code. Warning, its HEAVY
73's Bob W7VZX
Date: Sun, 11 May 1997 23:48:14 -0400
From: marty@aa4rm.radio.org (locale for Marty Reynolds)
Subject: Re: FT: Knight / WE 377As
liar liar - pants on fire
I told you my WE377 was for sale too! The deafening silence was due
to oxygen introduction into the Bogen's power transformer primary winding.
That caused the attendant loss of a fuse.
And I said I'm not going to risk any more collectible audio gear on
single-ended WE 377 design revamps.
So after yours finds a buyer, give same my address & ur appologies.
Perhaps a PP-design might best exploit the rare, exquisite red-top design.
M
End of glowbugs V1 #29
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Created by Steve Modena, AB4EL
Comments and suggestions to modena@SunSITE.unc.edu