[Central-Electronics] Frequency hopping 100V

[K6jek at aol.com]

My 100V jumps 20 - 50 Hz, then jumps back, jumps the other way.   I thought, 
oh my, time to rebuild the PTO but lo and behold it's not the PTO.   I plugged 
a very stable signal generator into VFO IN and used it in place of the PTO.   
The frequency still hops.

I'm about to begin detective work on the two other oscillators but would 
appreciate advice from anyone with tips or experience with this strange 
phenomenon.

Jon, K6JEK