03-14-2011, 12:36 AM
Not sure if you ever got the answer to 170V at speaker windings........ I assume you are measuring the voltage at the field winding and not the audio output transformer. If there is no load on the B+ supply, then the voltage at the field winding should be close to the PEAK of the line voltage. At 120 VAC input, the peak voltage is 170 Volts (120 x 1.414). This PEAK will be stored in both capacitors around the field coil and will drop as current is drawn. One way to see if the 50L6 is drawing current is to measure the cathode voltage (voltage across the 130 ohm resistor). If the voltage is zero, then no current is flowing.
I also have a Philco 42-327. In the back of the set, attached to a wire that ties to the bank of tuning capacitors is a small sheet metal piece approximately 1.5" x 2". This piece has a hole in it (approx 1/2" dia) with jagged edges and is attached to a cardboard insulator. Does anyone have an idea what this piece is used for and/or where it should be attached. Mine is simply loose inside the back of the radio.
Bob
I also have a Philco 42-327. In the back of the set, attached to a wire that ties to the bank of tuning capacitors is a small sheet metal piece approximately 1.5" x 2". This piece has a hole in it (approx 1/2" dia) with jagged edges and is attached to a cardboard insulator. Does anyone have an idea what this piece is used for and/or where it should be attached. Mine is simply loose inside the back of the radio.
Bob