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Philco 640 Electrolytic Voltage Ratings?
#3

According to the schematic (attached) #'s 74 & 75 are attached to the rectifier filament which is supplied voltage by winding 6-7. According to the power transformer data that winding supplies 5 volts at 2 amps. Do I really need a 500V rated e-cap for these?

Plate voltage for the 85 tube should be 102V. That voltage then goes through the primary winding in the audio transformer and to ground through one of the 2 uF e-cap of #68. Do I need a 500V rated e-cap for this as well?

I'm not sure what voltage is hitting the other 2.0 uF or the 1.0 uF.

Just trying to keep cost of replacement parts down.

- Geoff


Attached Files
.pdf Philco 640 Schematic & Voltages.pdf Size: 569.29 KB  Downloads: 194


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RE: Philco 640 Electrolytic Voltage Ratings? - by Geoff - 06-10-2014, 04:29 PM



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