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Philco 70 Pot replacement
morzh
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#4

10-29-2013, 05:07 PM
Well

Same exact resistor, 250/5000 Ohm is in Philco 20.
Now I suspect the points F and G on that resistive divider, where the missing pot section used to be, are shorted together or maybe there is the sub resistor of 250 Ohm in between them. Otherwise nothing would work, that thing completes the Field coil circuit.
I also suspect that the first two tubes' cathodes that used to go to the wiper of that section are wired to the ground (chassis) somehow or maybe to that E-F connection point. Otherwise they would not work either.

Right?
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Messages In This Thread
Philco 70 Pot replacement - by kadulazarini - 10-27-2013, 02:43 PM
RE: Philco 70 Pot replacement - by morzh - 10-27-2013, 04:27 PM
RE: Philco 70 Pot replacement - by kadulazarini - 10-27-2013, 08:22 PM
RE: Philco 70 Pot replacement - by morzh - 10-29-2013, 05:07 PM



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