Re: Full-Range IF Selectivity; The Hammarlund Variable Crystal Filter
As an aside to this fascinating discussion, I see from the circuit diagram that the differential cap has to have the rotor and shaft floating, since one side has to be earthed. The few differential caps I have are all conventional, with earthed shaft. With quite small capacitances involved, doesn't this lead to a few hand capacitance effects when operated, unless a long insulating shaft is used with an insulated capacitor mount? Or have I missed something?
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