>
>Hi Bill,
>
>> Previous posts indicate that the numbers Rich used below were NOT for a
>> G2DAF Amp, but for a "bastardized" version. Rich has a "Thing" against the
>> so-called G2DAF, and his comments are to be taken with caution.
>>
>> Bill-W4BSG
>
>I don't think the G2DAF is a good system either. It has to be, at
>the very least, very unreliable for IMD quality.
>
>It does everything wrong I can possibly imagine. It loads the exciter
>with a time-varying and power sensitive load, the screen voltage
>moves all over the place, and there must certainly be phase-shift
>between the screen voltage and the drive voltage.
>
>Probably the only thing that "saves it" in some cases is the high
>amount of negative feedback.
>
There is no negative feedback.
>I'm sure there are cases where it will work, but then I've even seen
>class C PA's produce "acceptable" IMD at certain power levels and
>certain tuning conditions.
>
>IMO, the fewer G2DAF systems on the air the better off we all
>are....even if some seem to be "OK". It has to be one of the
>poorest circuits available for a linear amplifier, short of out-and-out
>self-biased class C.
>
>
>73, Tom W8JI
>w8ji@contesting.com
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
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>Problems: owner-amps@contesting.com
>
>
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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