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37-9 poor reception at low frequencies
#1

All electrolytic, tubular, and Bakelite caps are new. Also new tuner support bushings. There is some reception at the higher end of the AM band, none below about 700Khz, and none that I can tell on SW bands.Cathode resistors on 6A8 and 6N7 check ok. R2 OK.
I am able to force a signal from my generator, perhaps it just needs a better antenna than i'm providing. Open for suggestions at this point.
Thanks
Cornell
#2

I would do the alignment. You maybe able to tell whats not aligning properly. Also check plate and screen grid voltage on the RF and mixer. Clean band switch. Do you see any black coils? Lightning Bad mica cap will cause this issue. I'm assuming that the tube test GOOD
GL
Terry
#3

Agreewith all, but also check to see if tuning cap shorts at or below 700K. Usually one of the outside rotors is bent or there is some dirt . You should be able to slide a piece of paper between rotor and stator and locate where it "catches", or use ohmmeter. This happens frequently on the lower side, as the fins are nearly entirely meshed.




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