01-28-2023, 08:55 PM
I have been slowly working away on this radio. I was initially thrown by the unusual power cord arrangement. It looks like there are too many wires. Its not a curtain burner resistance wire (the extra brown wire with the tape on the end) but I think it was part of the antenna loop. The loop or whatever it was part of is long gone so the only antenna now is the external antenna connection.
[Image: https://www.dropbox.com/s/2r4676d9fyz4li....jpg?raw=1]
Some of the other General Television radio schematics do have a power cord antenna system but I could not find a schematic with this tube layout and the power cord antenna. The model 19 and 52 schematic is for the most part correct for the radio although I primarly simply replaced resistors and caps with the values that were in the set already.
[Image: https://www.dropbox.com/s/167p5vnail04cu....jpg?raw=1]
After getting it back together and restringing the tuner it was playing although with extremely low volume. Even my SSTRAN broadcast was barely audible at full volume so I started going through the circuit wire by wire. Lo and behold one of the resistors was 150 ohms but should have been 500k. Swapping that out and it now plays normally
I'll now start working on the cabinet and doing a little more clean up. With a bit closer inspection I now know why that loose knob that went missing in the beginning. The set screw threads in the knob are stripped. I think I have three choices: a) find a new knob, b) drill and tap with a larger set screw or fill the existing hole in the knob (epoxy putty?) and drill and tap with the existing size set screw. Would appreciate any experiences anyone has had trying to fix a stripped set screw thread.
[Image: https://www.dropbox.com/s/2r4676d9fyz4li....jpg?raw=1]
Some of the other General Television radio schematics do have a power cord antenna system but I could not find a schematic with this tube layout and the power cord antenna. The model 19 and 52 schematic is for the most part correct for the radio although I primarly simply replaced resistors and caps with the values that were in the set already.
[Image: https://www.dropbox.com/s/167p5vnail04cu....jpg?raw=1]
After getting it back together and restringing the tuner it was playing although with extremely low volume. Even my SSTRAN broadcast was barely audible at full volume so I started going through the circuit wire by wire. Lo and behold one of the resistors was 150 ohms but should have been 500k. Swapping that out and it now plays normally
I'll now start working on the cabinet and doing a little more clean up. With a bit closer inspection I now know why that loose knob that went missing in the beginning. The set screw threads in the knob are stripped. I think I have three choices: a) find a new knob, b) drill and tap with a larger set screw or fill the existing hole in the knob (epoxy putty?) and drill and tap with the existing size set screw. Would appreciate any experiences anyone has had trying to fix a stripped set screw thread.
