Greetings all...

I recently cleaned the pots on this amp, and all was working fine for a short while. Then the reverb just dropped out when I was playing.
I could hear the tank echoing then that stopped too.  I tried a different tank.. but still no luck.

I checked the RCA connectors and they look ok. Also took the amp apart and inspected the PCB and connections.
I don't see anything that looks disconnected or damaged. I don't know how to test the op amp itself.

Could I get some suggestions to isolate and possibly repair this problem??