Hi guys, I have a problem with my '78 2203, no sound is coming from the amp after checking all the connections, the power tubes filaments don't become red and the very small amount of hum, typical after powering up the unit, does not appear. Could this be the OT?!? I've been using the amp until this morning without problems and suddenly, this afternoon it stopped working
It won't work if the heaters aren't working, I would check and make sure the heater circuit is at 6 volts I can't imagine all tubes going at the same time....
Am I wrong or if it was a fuse no power would go through? The unit powers up, apparently, I mean the power switch lightens up...
IMO it sounds like a heater circuit problem. Same thing happened in my attenuator recently. My power switch still lit up too, but the power amp was not working. There may also be a defective power tube associated with it.
The first and easiest thing to do is to check both fuses if you can confirm that the fuses are good you can start to check voltage levels inside. I doubt that your OT went bad and now the heaters don’t work.
The pilot light runs off the heater string: If the heaters are not lighting up you will need to check the heater voltage on all the tube sockets.
Ok guys, thanks for your responses, you were right with the fuses, the HT is blown. To be honest, yesterday I was playing with preamp tubes, so maybe I did something I shouldn't... I'll check tomorrow with a new fuse and get back, thanks for your help anyway!
