"Has to be" Tom - you assume because you actually do not know. Why do you
not try to build a few copies of the ones other hams build and that worked
fine and then you will find out why they were so succesful? Theory is one
thing - practise another, right? Or: "the proof of the pudding is in the
eating as the saying goes.... ". Or in Deutsch something like: " Grau ist
aller Theorien Anfang ... " - nicht war?
Prosit de Hans SM5KI
----------
>Från: "Tom Rauch" <w8ji@contesting.com>
>Till: amps@contesting.com, Bill Aycock <baycock@HIWAAY.NET>
>Ämne: Re: [AMPS] Re: G2DAF Amps Circuit
>Datum: ons 25 okt 2000 19.00
>
>
>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.
>
>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
>
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