03-06-2008, 11:47 PM
Hi
Odd that your Rider's does not give specs for the field coil? Usually Rider merely copied the service bulletins provided to him by Philco, and the bulletin for Model 38-12 shows a field coil of 1500 ohms.
Specs for the power transformer, per 1941 Philco parts catalog:
High voltage secondary: 516 volts center-tapped, 50 mA DC
Filament winding: 6.3 volts @ 2A
Specs for the audio output transformer, per 1946 Philco Quick Selector Parts Directory:
Primary impedance 8000 ohms; secondary impedance 3.5 ohms; 3 watts; turns ratio 44:1.
You should seriously consider buying a copy of the factory service info from Chuck; he not only supplies a copy of the original Philco service bulletin, but also an extra-large copy of the schematic, and includes any pertinent changes.
http://www.philcorepairbench.com/schematics.htm
MUCH better info than found in Riders, and at a reasonable price.
Odd that your Rider's does not give specs for the field coil? Usually Rider merely copied the service bulletins provided to him by Philco, and the bulletin for Model 38-12 shows a field coil of 1500 ohms.
Specs for the power transformer, per 1941 Philco parts catalog:
High voltage secondary: 516 volts center-tapped, 50 mA DC
Filament winding: 6.3 volts @ 2A
Specs for the audio output transformer, per 1946 Philco Quick Selector Parts Directory:
Primary impedance 8000 ohms; secondary impedance 3.5 ohms; 3 watts; turns ratio 44:1.
You should seriously consider buying a copy of the factory service info from Chuck; he not only supplies a copy of the original Philco service bulletin, but also an extra-large copy of the schematic, and includes any pertinent changes.
http://www.philcorepairbench.com/schematics.htm
MUCH better info than found in Riders, and at a reasonable price.
--
Ron Ramirez
Ferdinand IN
