Gonna make sideband sound like doo-doo. Bonus is that it's also a good way to clobber both the radio finals and/or linear transistors. Sideband transmit will work them to death unless the mike gain gets played like a violin. Doesn't do any favors for AM-audio quality, either.
There is a 'back door' fix to prevent this if you don't have a supply of 2SC945 to install at Q39. Pull the transistor at Q57. This is also a 2SC945. Q57 is the sensing transistor for the AM-only modulation limiter. Opens up AM, but when a transistor is put back into Q39, this restores sideband limiting/ALC. If you properly adjust VR13, naturally.
If you fancy using sideband, this is a lesser-evil solution.
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