Hi everyone, thanks for reading. I have an anthem MRX 710 receiver that just recently shutdown itself every time I tried to power it up. I performed a visual inspection and nothing obvious like open caps or burned components were observed. I spent several hours looking for a service manual or schematic and that seems to be a highly closed guard secret since none was found. I contacted Anthem and unfortunatly they do not sell replacement parts. They required you to send them the receiver (shipping is really expensive due to the weight) instead. I feel comfortable doing basic electronics troubleshooting, so I will really, really, really appreciate if anyone can provide some hints/suggestions/ideas about what to check/test. Your help/ideas will be greatly appreciated.
Maybe provide a few photos so we can take a look? Not sure if we're dealing with a class AB or D amp here...
Looks like class AB, so in that case, you want to figure out if it's a protection circuitry fault, or a real amplifier fault. Maybe try to measure the output of each channel to see if there's any large DC voltage component present when powered on. Should be able to do that on the PCB on the middle leg of the big white emitter resistors.