[Kenwood] MRF485 substitution
Dr. Gerald N. Johnson, electrical engineer
[email protected]
2002年9月30日 15:14:21 -0500
Dropping the driver supply voltage to 12 volts may end up with too much
mismatch to the PA input to allow that driver to drive the PA to full
output. When choosing a supply voltage and an transistor, remember that
due to the swing of the transformer, the transistor has to handle twice
the DC at RF peaks. So a transistor rated for 28 volts peak is only good
for a 14 volt supply. Fortunately some transistors have reserve built
in, but that's not guaranteed.
73, Jerry, k0CQ
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Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.