[bluecap]

Hi folks, I'm in the process of restoring a Philco 40-120C and I'm finding the wiring to be a bit puzzling. According to the schematic, the filament resistor should be connected to Pin 1 (the heater of the rectifier tube 35Y4). However, it is attached to Pin 5 (a "no connection" pin in the tube) without a jumper from Pin 5 to anywhere else. Meanwhile, Pin 1 is attached to Pin 6 of the 7C6 tube (the tube's triode cathode). It all appears to be the original wiring. Any guidance would be greatly appreciated. Thanks.

[klondike98]

Let's try to sort it out. So we are working with the same info here's the schematic I have:
[Image: https://www.dropbox.com/scl/fi/mvw9qo0t7...xpxj&raw=1]

...and here's the pin out for the 35Y4 (only difference from the 35Z3 in the schematic is the center tap on the heater):
[Image: https://www.dropbox.com/scl/fi/xhbiio84h...3wc3&raw=1]

I agree that if the 132 ohm end of resistor #34 is connected to pin #5 of 35Y4 and there is no other connection to pin#5 (and no other connection to the end of resistor #34) the unit should not work. With all the tubes in place, what is the resistance reading across the power plug with the switch closed?

[morzh]

Is the tube in your radio actually 35Z3 or 35Y4, or something else?