{Collins} 32S-3 weak modulation

Now that power is sort of back to normal on my 32S-3 restoration, I need to fix the next problem: very weak sideband power out.

When I use my SM-1 mic or if I put a tone directly into the phone patch jack, even with the MIC gain control fully open, I get almost no ALC meter movement, and very little plate current.

I can trace the audio through audio amps/follower, through the balanced modulator, IF stage, mech filter, with a scope, but I can’t tell what the level should be.   If it were dead, it would be easy to trace.  It must be too weak someplace in this path.
Since I am getting good grid drive on all bands, this tells me that the problem has to be before the 1st mixer (where BFO signal is injected during TUNE and LOCK KEY).

Anyone had this problem, or have a record of what the audio/signal levels should be?


Grayson, KJ7UM

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