10-02-2015, 04:11 PM
>Amateur here. Me too I'm N3GTE.
Sorry I was looking at the Riders schematic and it doesn't show the wave trap. Philco made a bunch of different versions of the model 60 over it's 3 or so yrs of it's production run. To adjust it inject an signal in to the ant post at the IF frequency and adjust the trimmer for the WEAKEST signal in the speaker.
The oscillator circuit is a little different from the model 80. Now the great chase begins have to find where the electrons start and stop! Things to look for: Must have HV on pin 4 of the 6A7. If not feedback winding is open on the osc coil. If you do have hv on pin 4 you should have a few negative volt on pin 5.
You can still listen for it in another radio but the voltages will help pinpoint the problem.
GL
Terry
ps Whats an oscilloscope?????
Sorry I was looking at the Riders schematic and it doesn't show the wave trap. Philco made a bunch of different versions of the model 60 over it's 3 or so yrs of it's production run. To adjust it inject an signal in to the ant post at the IF frequency and adjust the trimmer for the WEAKEST signal in the speaker.
The oscillator circuit is a little different from the model 80. Now the great chase begins have to find where the electrons start and stop! Things to look for: Must have HV on pin 4 of the 6A7. If not feedback winding is open on the osc coil. If you do have hv on pin 4 you should have a few negative volt on pin 5.
You can still listen for it in another radio but the voltages will help pinpoint the problem.
GL
Terry
ps Whats an oscilloscope?????
