i aquired a non-functioning rf 250a2 punch amp a few years ago going into electronics eng. at college. I've been trying to troubleshoot it for a few years now but never really get much time to spend on it. The original problem i had was i wasn't getting any sound out, at school i injected some simlpe tones into the rca inputs to see if i was getting anything out using an o-scope. I think i've trailed it back to a few transistors but i'm unsure as before i could continue troubleshooting the transistors, the unit itself stopped functioning. Now the unit will not power on. I know i have power, it does not blow fuses, it just sits there. Anyone with some knowledge of these amps know where abouts in the circuit it's failing? I can't seem to find anything that shouldn't work via ohm checks. Anything info would help, thanks!