[R-390] R-390 RF Gain Control

[Steve Toth]

Try a 2 watt 5k pot with a 620 ohm resistor connected between the wiper and the TOP end of the pot (ungrounded)
with the wiper at the same end that the resistor is connected to (the TOP end) the value is 5k.
mid sweep of the wiper the value is 496.79 ohms (pretty close to 500 ohms).
Formula:  Rt = R1 x R2 / R1 + R2
P.S.  It was the balance control on a '65 Oldsmobile radio
- Steve  W7SJT

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    On Sunday, September 12, 2021, 08:29:59 PM MDT, Jacques Fortin <jacques.f at videotron.ca> wrote:  
 
 Renée,
I'm sorry but... check what that gives at mid-travel and CCW positions.
Reverse-log ?
Not really, I believe.

73, Jacques, VE2JFE

seems like one needs a 50K lin pot and a 6K fixed .. IIRC Renée K6FSB

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