I've replaced the filter capacitor on the P2000, and it's back to running smoothly again.
Nice graphics for the time:
Quoting a vcfred thread:
"The machine has a CPU board with a separate "terminal" board that is connected to the CPU board via a TTL level serial link, so the display looks like a dumb terminal to the computer."This guy
is repairing his terminal board, some useful information there, but there are full schematics in the manuals I posted.