>
>Rich says:
>
>>/\ A grid dissipation rating of 2w max. is not good news for g-g
>>operation. With Class AB1 grid-driven operation, grid dissipation is 0w.
>
>We usually think of g-g as being AB2 with triodes or triode connected
>tetrodes/pentodes. Does it have to be?
/\ no. the Collins 30S-1 is AB1 cathode driven.
> I've never
>seen an AB1 grounded grid design, but is there any reason why one couldn't
>drive
>something like a 4CX250 in g-g and
>keep it in AB1? I'd expect normal screen and grid voltages, and lower gain
>caused by the NFB.
>
>Or is there something blindingly obvious here that I've missed? - apart from
the
>fact that if you're going to the trouble of
>providing screen and bias supplies,
/\ screen and bias supplies are a 'piece of cake' for 4cx250s.
> passive grid has the advantage of not
>needing tuned input?
>
/\ except on higher freqs. The fly in the ointment with g-g is the more
critical tuned inputs.
>
cheers, Peter
- R. L. Measures, 805.386.3734, www.vcnet.com/measures.
end
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|