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OK, I am here with the set and trying to test a few things.
I made a little jumper so I could use my test socket on V11, the HOT, 12DQ6A. Pin 4 has 105V instead of 175. Pin 5 is just barely negative at -.15 instead of -45. So I think we can say the horizontal multi-vibrator isn't running. I did actually get a small Sains-Smart oscilloscope to look at the horizontal multi-vibrator wave form but without it running at all it seemed pointless to try it.
Looking at the power supply side of things, the junction of the rectifier diodes (M1 and M2) starts at 150V and drops to 126 as the set warms up. The output of M1 is 245V instead of 290. So I decided to see what the current passing into the set is. The schematic shows it as 270mA. Once the set is warmed up the output current reaches 350mA. So I guess the power supply is OK and something is dragging the voltages down.
The couplates, including K6 have been replaced. I have subbed another 6CG7. I routed the sound through the set. I can get some sound with the volume cranked and the local/distance switch set to distance. However, it is weak and distorted.
@old_coot88 I just tried to check L22. There are three tabs visible from the top. Between 2 of them I get essentially 0 resistance. Between either of those two tabs and the third, I get infinite resistance. I though I had a drawing/picture that showed the traces on the back of the PCB so I could see how it is wired into the circuit. I can't find it. I do have a parts set I could dig out and see how it measures there. You may be on to something!
Thanks for the help!
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