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Philco 87
#1

I recently aquired the radio and was very careful to check the power supply before powering it up. The main B+ is 290v but the voltage divider suplying plate voltages to rest of the tubes is 30v not the required 90. It looks like a bad capacitor accross the voltage divider resistor identified as (35). Where are the capacitors? #31 on the Rider schematic.
Any help would be appreciated!

Jim
#2

Jimony, look for a bakelite block structure in which the capacitors, I believe five in all, should be located. I believe thats the capacitor block that has a number of wires running from it . Ryders has the wiring layout.
Pat
#3

Hi,

Your set is a 1929 model and did not use bakelite block caps in production.

The large filter bank capacitor is the large square metal can next to the power transformer at the front right corner of the chassis. There may be a Philco part number, 3401 stamped on it somewhere. This metal-can cap has to be re-built, in similar manner to the metal can cap #27 (3080), under the chassis, which houses the two filament bypass caps.

You should also replace all the other wax-paper bypass caps and check all resistors as well.

All the original caps in the cans are non-electrolytic and you can replace them with newer 630 volt film type caps with no problem.




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