While overhauling the my 30S-1, I noticed the amp has no rf choke in the
filament/cathode circuit. The cathode/filament is connected directly to the
I find this unsuall since the filament transformer adds about 80-100pf more
capacitance to the input circuit. Although Collins designed the matching
circuits with about 220pf input, why not isolate the filament transformer? Most
other amps in similar configurations do.
I am not second guessing the engineers at Collins just trying to understand
Anybody have any comments?
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