Hallicrafters S-20R

[bob91343]

The capacitor plates are not shorted. I feel the problem is that the resonant circuit in the grid isn't resonating. Whether that's due to a bandswitch wafer or what, I have not been able to determine. I do get gain in the first stage. I just can't couple it to the mixer.

I took off the grid cap, put an 8.2k resistor from grid to ground, and clipped an antenna to the grid. Radio works well, so all from there on is good. It's driving me bonkers. I removed the two burned out rf coils and rewound the primaries (not a good circuit because if you inadvertently ground the plate of the 6SK7 while measuring it, you burn out the coil.). Still no action and the trimmers have no effect. (This rewind operation is not for the faint of heart. I had to drill out the eyelets holding the trimmer assembly and replace with screws later on. Putting things back together required a midget with telepathic communication.)

Do you have a parts unit?