[R-390] TR: Misrepresented RF gain Pot on E-Bay

Jacques Fortin jacques.f at videotron.ca
Sun Sep 19 17:45:12 EDT 2021


Hi Bill,

As I mentioned before, nothing can be done to make a 5K linear potentiometer behave as a 5K reverse-log one.
To K5SVC defense, it is not specified, or not easily found, that the RF Gain control on a R-390/390A have to be a reverse-log taper one, other than few obsolete military stock numbers.
I learn it the hard way...
Two of my R-390A came with linear pots mounted in (as replacements for the original ones) and the RF Gain control operation was very far from satisfactory.
I explained why in my previous postings.

73, Jacques, VE2JFE



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