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Philco 71 abnormal filament voltages-low volume
Steve Davis
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08-04-2024, 06:48 PM
If stations only come in while touching the grid cap of the RF tube, that is a pretty sure sign the antenna transformer has an open winding. On to the filament voltages. Be sure to use the AC scale on your meter, read from filament pin to filament pin. not filament to chassis ground. Last, the plate voltage of the 1st audio is probably OK. The plate is supplied through a couple of high value resistors, your modern meter does not load the circuit as much as the meters used back in the day, giving a higher reading.

Steve
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RE: Philco 71 abnormal filament voltages-low volume - by Steve Davis - 08-04-2024, 06:48 PM



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