01-31-2024, 11:54 PM
mancave,
If you have a signal generator, you might try injecting an audio signal into the grid of the 7A7, where the audio for the phono goes in [pin 5] to see if the signal gets lost in or after the phono pre-amp 7A7. Or if the switch isn't making good contact. Or, again, try the tip of a soldering iron on pin 5.
The Philco library has a better schematic and information about the radio itself, but I don't see the phono transformer on the schematic, just in the parts list.
https://philcoradio.com/library/download...6-1947.pdf
If you have a signal generator, you might try injecting an audio signal into the grid of the 7A7, where the audio for the phono goes in [pin 5] to see if the signal gets lost in or after the phono pre-amp 7A7. Or if the switch isn't making good contact. Or, again, try the tip of a soldering iron on pin 5.
The Philco library has a better schematic and information about the radio itself, but I don't see the phono transformer on the schematic, just in the parts list.
https://philcoradio.com/library/download...6-1947.pdf
