[RGK20m3]

I have been reading John Rider’s book and understand the theory, also have been using his narrative to try to come up with a diagnostic process. Have already checked voltages on the 6K7 magnetic tuning amp and have 34v on the plate and 24v on the screen; the voltages given for the 38-116 show they should be 40/20. The voltages that I measured were with the radio tuned to a strong station (I measured before I read the note of no signal). There are no published voltages for the 38-690.
What voltages should I expect to see going positive/negative on the defeat switch? 0-5v?
I am trying to come up with a way to rough tune the magnetic tuning circuit. My understanding is that 85A(the hex) moves the core, and there is a trimmer concentric that tunes the primary- then the other two trimmers tune the secondary (for minimum signal). The two issues that I see is that I can’t seem to tune the primary, which would defeat the AVC, making the minimum signal moot.