In a message dated 97-09-06 09:48:22 EDT, you write:
<< "Power on a Budget" by W6FR was a very good article, but I'd suggest
a few changes.
First, the auto bias circuit has a slow rise time because the 1 mFd
capacitor at D1's cathode has to charge through a 1.5 k resistor in
series with the reactance of a 33 pF capacitor. On lower bands, the
time constant is very slow, and that will cause slow bias removal on
the leading edge of speech, and class C opertion for an instant of
time. The impedance at the output of D1 needs to be greatly
increased, meaning a much larger value of hang time resistor
and much smaller value than the 1 mFd cap should be used.
>>
Hi Tom,
You seem to contribute to this reflector quite abit....
I have no knowledge of Legal limit amatuer amps......
But what/which AMP would you pick from the QST article as it
is written on that bases alone? As there are probably quite a few out here
like me who would use the article to make a decision.
Just curious.....Measures and that other expert might want to select one out
of that
article and tell us why they choose it.
73 de KR4DA Bob LAwrenceville GA
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