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City: Chicago, IL
I just made some measurements.
With good volume
RF AVC grid voltage = -1.1
IF AVC grid voltage = -0.56
When volume drops, the voltages get less negative which should boost gain.
RF AVC grid voltage = -0.7
IF AVC grid voltage = -0.23
So it seems gain is being lost somewhere in the RF/IF front end and the detector/AVC circuitry is working properly.
(This post was last modified: 10-26-2021, 10:19 PM by Bob Andersen.)
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RE: Philco 90 restoration - by Bob Andersen - 10-26-2021, 10:18 PM
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