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37-670 capacitor questions
#10

There are no DC voltages near 1200 volts in your radio, but there might be some AC spikes that run high enough to warrant that high working voltage. Caps on the plate of the output tubes, like your 73 and 74, are often high voltage caps for that reason.

I don't know where in the radio your 110 pf caps are unless they are 42 and 44, so I can't say why they need such a high WV.

Micas in the 3 dot package are all 500 V. In the 6 dot packages they can vary a lot. Default with no color in the voltage dot is 500 Volts. I recently saw a 100 volt mica in that package.

Check the change notices when you get the schematic from Chuck. That might tell you if Philco made a change in the value of 73 and 74 at some point.

John Honeycutt


Messages In This Thread
37-670 capacitor questions - by Tom Hamilton - 01-23-2014, 10:15 PM
RE: 37-670 capacitor questions - by hsusmann - 01-23-2014, 10:26 PM
RE: 37-670 capacitor questions - by morzh - 01-23-2014, 10:27 PM
RE: 37-670 capacitor questions - by Tom Hamilton - 01-23-2014, 11:08 PM
RE: 37-670 capacitor questions - by morzh - 01-24-2014, 12:36 AM
RE: 37-670 capacitor questions - by Tom Hamilton - 01-24-2014, 05:31 PM
RE: 37-670 capacitor questions - by OldRestorer - 01-25-2014, 07:57 AM
RE: 37-670 capacitor questions - by Tom Hamilton - 01-25-2014, 01:09 PM
RE: 37-670 capacitor questions - by Warren - 01-25-2014, 03:11 PM
RE: 37-670 capacitor questions - by Raleigh - 01-27-2014, 12:38 AM
RE: 37-670 capacitor questions - by exray - 01-27-2014, 06:28 AM
RE: 37-670 capacitor questions - by Tom Hamilton - 01-27-2014, 12:44 PM



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