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Philco 40-140 Field Coil Replacement
#4

No, just that there would be need to increase the filter capacitor value after the first resistor to minimize hum. Long ago chokes were cheaper than filter capacitors, and permanent magnets did not exist. What we want is a smooth DC curent for the set. So the smoothing capacitors must be a little larger, first one not more than 20% of original, second one not more than 30% of original nominal value. OK and preferred to use much higher voltage values. Observe polarity!


Messages In This Thread
Philco 40-140 Field Coil Replacement - by radiola - 09-05-2012, 12:21 AM
RE: Philco 40-140 Field Coil Replacement - by codefox1 - 09-06-2012, 02:09 AM



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