[Amps] 1625

[Carl]

I believe that CQ carried the initial article and showed 6AG7's, 837's 
and modified 1625's. Id say late 50's or early 60's also.

Looking thru some notes, I try to never throw things away, packed with 
those tubes is that I first used a 10B to drive a single 1625 which 
drove the 4, all in GG. Later on I used a 20A and just drove the 4. None 
of that lasted long as I soon had a HT-37 and followed by a 100V in 65. 
Apparently I never fried those tubes., never remember any tell tale 
glow. I still prefer the sound of a phasing rig.

Carl
KM1H




----- Original Message ----- 
From: "Glen Zook" <gzook at yahoo.com>
To: "'Edwin Karl'" <edk0kl at centurytel.net>; <amps at contesting.com>; 
"'Carl'" <km1h at jeremy.mv.com>; <garyschafer at comcast.net>
Sent: Thursday, February 12, 2009 12:30 PM
Subject: RE: [Amps] 1625


>I pulled my original SSB Manual and you are correct, the original "Four 
>In Line" was grid driven.  There was an article in QST in the late 
>1950s or early 1960s that told how to convert this linear (or build a 
>new version) using grounded grid.  The instructions for modifying the 
>1625 tubes was included.  For some reason, I modified some 1625 tubes 
>but never got around to building the linear!  This was when I was in 
>high school.
>
> I found a couple of those tubes when I was trying to clean up the 
> shack a few months ago!
>
> Glen, K9STH
>
> Website:  http://k9sth.com
>
>
> --- On Thu, 2/12/09, Gary Schafer <garyschafer at comcast.net> wrote:
>
> The "four in line" was four 1625s mounted in line that were grid 
> driven in push pull parallel arrangement. Each side of the push pull 
> circuit had two tubes in parallel.
>
> Getting old when you remember this stuff.
>
>
>
>