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Field coil on Philco 38-12
#1

I have begun restoring a Philco 38-12 radio and have a question that I hope I can get an answer to on the phorum The speaker in this radio uses a field coil with a resistance of 1.5k ohms according to the schematic. I have completely disconnected the coil from circuit and when I measure the resistance I get approximately 6k ohms on my multimeter. I have been told that the 1.5k ohms shown on the schematic is the impedance of the coil and not the DC resistance. I restored a Philco 39-6 and the schematic showed 1.7k ohms and the coil showed approximately 1.7k +/-. So my question would be, is the coil shorted and needs replacement, or is it ok as it is?
#2

if anything, DC resistance is smaller than the impedance to AC current.

If it says 1.7K, it should measure 1.7K. Not 6K.

A shorted coil would be 0 Ohms, not 6k.

If it measure 6K, it is possible it is a different speaker altogether or the coil is bad.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.




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