Schematic diagram Joule Electra OPS-1

can you specify/describe problem? lots of them can be troubleshot with no schematics.

i repair nearly all band, live sound and studio equipment 95% with no schematics. i also play instruments(guitar, bass keyboards) but i suck on that and prefer to help bands recording, performing, setting up proper live or studio sound, tuning their instruments and fixing their broken and abused amps, pedals, processors etc... hi-fi repair (especially most of SET tube amps designed by amateurs) is substantially less sophisticated.

and yes have had many posts helping to ID and get rid of equipment problems without even looking at unit or schematics.