Hi Robert,
It’s easy to grab the frequency with a scope probe from the center pin of the pot in the carrier balance section. You’ll need an accurate counter that should be tide to a gps frequency standard.
With the audio generator you should have no more than 20mV, mine will not go any lower than 34mV. Once that’s set you’ll adjust your power at the mic gain pot located right behind the meter on the skinny PCB, it’s the far left pot. Audio set for 1khz turn mic gain pot for 50watts. Then change to 300hz and adjust each side band for 12.5watts.
For me this never really adjusted correctly for what ever reason, do I just set the frequency instead. If you have issues getting to the frequency’s you’ll need to replace the 39pf to a slightly lower value, 20 or 10. Actual frequency should be in the middle of the trimmer frequency swing. These xtals are old and are drifting. On my AM PCB I had a bad xtal no out put on AM.
When I adjust this way the audio sounds the same when switching from lsb to usb.
Be interesting to hear from others on this,
Michael
Michael K.