Amps
[Top] [All Lists]

[Amps] Grounded grid 8122's

To: Ham-amps <amps@contesting.com>
Subject: [Amps] Grounded grid 8122's
From: Herzog <herzog@frontiernet.net>
Date: Tue, 21 Jul 2009 21:00:00 -0400
List-post: <amps@contesting.com">mailto:amps@contesting.com>
I dont believe there is any way to run a 4CX250 style tube in GG without
destruction. Very few tetrodes have the necessary grid dissipation required.
===========
When our tube vendor became difficult, we hung the idea of using stock 
8122 tubes.  However we burned out a lot of grids before inventing a 
circuit that measured the grid current, and shut down fast enough to 
save the tube.  The worst case was when the driver was turned on, and 
someone or some fault shut the high voltage off to the 8122's.  The 
circuit shut the transistor driver down fast enough to save the tubes.
The vendor saved his day by throwing together stock parts to make the 
tubes used in the AM???? cheap enough to use; so the patent never filed, 
and the circuit is  burried in some engineer notebooks.  BUT it can be 
done, and just not wanted or needed.
       There is no secrecy, I just don't recall some, and too lazy to 
look it all up.  Wil  K 2 L B
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>