Hi guys, I'm back with a new AVR problem. Another junkshop find, this time a Denon AVR 2113.
When I first opened it up, the standby board was in a state. The TOP258MG had literally blown its lid, and there were badly damaged tracks etc. Anyways, I rebuilt that, and got the standby supply back.
While waiting for parts to arrived, I removed the main amp pcb, and found the FR channel had blown its fuseable resistors, its emitter resistors were open, and the two main output transistors were short. I replaced these components, checked the rest of the amp pcb, and reinstalled everything.
So this is where I am now: With everything plugged in and connected, the receiver will try to boot, but can't. It just clicks on and off constantly. Now if I unplug the power connector (CP403) from the amp pcb, the receiver boots up without any issues. So I thought there must be something wrong with the amp. Pulled it again, compared measurements, nothing. Can't find anything obvious.
I then measured the output of D4008 (bridge) that supplies HIGHB+ and HIGHB- and when the receiver boots, both HIGHB+ and HIGHB- climb to roughly 55v. When I power down, HIGHB- holds its 55v for ages, whilst HIGHB+ rapidly loses all its voltage. I'm not sure if this is telling of something or not? I'm thinking that perhaps this is a power supply issue and not an amp issue. Thoughts?
Thanks in advance!