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? Obviously somewhere in the power supply?
I can't seem to find anything that shouldn't work via ohm checks, atleast bad resistors. I'm unfamiliar with the circuit protection of these amps, perhaps a bad transistor would keep it from turning on?