>>Any problem using 500 volt ceramic disc caps for the larger values
and
>>silver mica for the smaller ones
I'd worry about the current rating of disc ceramics. If you have 100 watts
in 50 ohms, that's 70 volts rms. The reactance of 3300 pF at 1.8 MHz is
about 27 ohms, so there's getting on for 3 amps in that capacitor. If you
don't run contests, SSTV, RTTY, or AM, you may well get away with it.
Doorknob ceramics should be OK; I'd be a bit dubious about using silver
micas. It depends on whether you want to push ratings in the good ole' ham
tradition, or go conservative for reliability - a choice that gets a bit
like the transformer discussion we had earlier on this week. The big mica
compression trimmers should be OK, though, even CCS AM.
73
Peter G3RZP
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