R: [AMPS] Amplifier for cw only-question.

[Maurizio Panicara]

-----Messaggio Originale-----
Da: Chip Owens <owens@atd.ucar.edu>
A: <amps@contesting.com>
Data invio: marted́ 28 settembre 1999 21.41
Oggetto: [AMPS] Amplifier for cw only-question.


>
> If one uses an hf power amplifier for cw operation only is there any
> good reason to operate it in AB1, AB2, or class B? Wouldn't class C
> operation yield higher efficiency and actually make QSK operation
> easier to implement?

Yes, the efficiency is higher but the gain is probably smaller.


>
> Also, I'm curious if anyone out there is using the 3CX1200Z7/YU-181 in
> a homebrew amplifier. With its grid terminal brought out to a large
> circular flange on the tube base it would make an essentially zero
> impedance grid-to-ground connection. The data sheet mentions use of the
> SK-410 socket, but no chimney is mentioned. Is this series of tubes,the
> 3CX1200A7, 3CX1200D7, and 3CX1200Z7 a good choice for a homebrew amp
> over something like an 8877?
>

The 3cx1200A7 I used had a tendency to self oscillate.
I never used the 3cx1200Z7 (1300W plate diss.) but it should not have the
same problem.
Personally I consider the 8877 another category of tube, much better !

> This is my first posting to the reflector. Do I need to put on my
> flak-jacket before reading replies?
>
> Chip, NW0O



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