Hey, I have a problem with the Onkyo amplifier, as soon as I turn it on, it waits a second then a bunch of relays click and it switches off completely, then the standby LED is blinking, indicating it went into protect mode. Did anybody have that problem with this amplifier? I checked all fuses, they read okay. When I take out fuse F6901 and F6902 out, the amplifier will turn on and stay on, and I can operate it normally except obviously no sound comes out of it. Initial measurements show no shorts across output channels, no bad emitter resistors, nothing obvious. Measuring output of bridge rectifier D6901 when switchin on shows 45V, then a relay clicks and it goes to 91V, and then another relay clicks and everything shuts down and goes into protection mode. If I put a fuse in while it's working, it sparks a little bit then goes into protect mode again in a second or so. It does not blow those 8A fuses though, and I was unable to measure any significant current across the fuse holder with multimeter, showed max 0.1A
I have worked on amplifiers before with success, but this one has two of some sort of hybrid output modules (marked STK442-530 and a bigger one STK443-530) I assume for speaker set A and set B, and I haven't got a slightest idea how to check for bad output stage on this thing, has like 18 legs. Any help? Attached service manual.
I have worked on amplifiers before with success, but this one has two of some sort of hybrid output modules (marked STK442-530 and a bigger one STK443-530) I assume for speaker set A and set B, and I haven't got a slightest idea how to check for bad output stage on this thing, has like 18 legs. Any help? Attached service manual.
