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[Amps] Any designs for 4CX1000A on 2m ?

To: 'AMPS' <amps@contesting.com>
Subject: [Amps] Any designs for 4CX1000A on 2m ?
From: "Dr. David Kirkby" <david.kirkby@onetel.net>
Date: Mon, 06 Jun 2011 21:24:58 +0100
List-post: <amps@contesting.com">mailto:amps@contesting.com>
Are there any published designed for 2m linears using the 4CX1000A tube? I 
tried 
to build an amp with a pair of them in push-pull grounded screen, but it never 
worked well. Now thinking about something more modest - a single tube, using a 
conventional socket with cathode grounded.

I know there was a design in the ARRL handbook for a single-tube grounded 
screen 
amp, which gave me the idea of a push-pull amp, but I never got it working very 
well (it was drawing positive grid current with an output of only 300 W. Had I 
pushed the input power, it would have probably damaged the tubes).

I've seen comments that the grounded screen amp in the ARRL handbook was not 
such a good idea, which is making me think it might be better to go along the 
route suggested in the data sheet. i.e.

cathode at DC ground
grid at -60 V
screen at +325 V

I've also seen a design on the web which ties the screen and grid together, to 
use the tube as a triode, but again I want to avoid that.

Are there any decent designs for a 2m amp with a conventional usage of voltages?

I recall John Nelson, GW4FRX telling me the 4CX1000A presents more problems to 
hams than any other tube, so I don't think it's the best device ever made, but 
I 
happen to have quite a few sitting around collecting dust.

Does anyone have a socket for one? I built the grounded screen sockets myself 
(had access to a workshop at the time). But I want to buy an Eimac socket, with 
the screen decoupling capacitor for this.

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