Try Stewart Warner 300 series schematics available here on nostalgiaair. They should be similar.
C battery voltage was - 4 1/2 volts. This would be right for an output tube with 90 volts on the plate.
Original cap may have bypassed B+ voltage? They didn't use electrolytic. Check the circuit and if the cap is connnected to a battery voltage use .47 or 1 mf. Value isn't critical.
Norm
:After an exhaustive search I have been unable to locate a schematic for this radio.It is a 5 tube (01A's) battery set.I have two questions:It has one capacitor under the chassis that is unmarked. What would be a good ballpark size cap to replace it with and if it would be electrolytic, how would I orient polarity?. Also the voltages are marked on the terminals with the exception of the "C" battery. What would this voltage be? Any help will be greatly appreciated as it is a beaut and all other componants test good. Many thanks, Jon.
Norm, Many thanks for the info, will let you know how it turns out. Regards, Jon.