[Amps] GU43B amp for 2m ?

[G0RUZ Conrad]

Yes its a copy of the 4CX1000A amplifier that was published in the ARRL
handbook. I have built this amp and used a 4CX1500B in it, the key is to
ground the screen. One other caveat is that there is a strange mode set up
in the anode compartment. I cured it by placing a big (100w) 120 ohm carbon
resistor stood off the chassis two insulators. I had seen this in some Band
II cavity amplifiers and it completely cured it, I was astonished at the
time.

A far better prospect is to use a 1/2wl line over the anode cooler similar
to this:

http://www.nd2x.net/OH3AWW.html

No nasty PTFE sandwiches to flashover and really good efficiency. I would
still ground the screen and operate the cathode and g1 at minus g2
potential.

73

Conrad G0RUZ

> -----Original Message-----
> From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com]On
> Behalf Of Traian
> Sent: 26 October 2004 16:38
> To: amps at contesting.com
> Subject: [Amps] GU43B amp for 2m ?
>
>
> Hi all,
>
> Pictures from a VHF amp using the GU43B tetrode:
>
> http://www.ok1kvk.net/pa_gu43b.htm
>
> I like the HM socket, the way how the use of a hard to find socket was
> avoided.
> May this to be a 2m amp, as I think?!
>
> 73,
> Traian
>
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>