I have picked this up from the bay, with a blown center channel.
Easy fix, right?
I have found all the parts, that are needed to be replaced.
All done, I have tested the mainboard twice and the pre-amp board twice.
All is good. I have started measuring the idle current and it was going up slowly(which is good). Around 5mV, suddenly it was dropping toward 0, and it reached 0.
I have took everything apart, and measured everything again. I did not find, anything wrong. I put it back together and this time, the idle current started going up way to fast to my liking and of course, it started smoking at the center channel pre-amp board. I have turned it right off, to don't cause bigger damage.
Found a 2.2 Ohm resistor(R6292) near the connector(emitter resistor for the TTA transistor-Q6102), with very high resistance. I have replaced it, could not find anything else wrong.
I have tried it again, after inspecting everything again. Still smokes.
I would need help, tracing down why it keeps smoking.
I have also replaced C6022/50V(capacitor between the two TTA/TTC transistors, just in case). I have to recognize, that I did not replace TTC, because it wasn't blown(initial repair), only the TTA.
In these amps, almost every time, blow the same components.
Capacitor has the right orientation, I have checked.
I would appreciate any help.
Tibor
Easy fix, right?
I have found all the parts, that are needed to be replaced.
All done, I have tested the mainboard twice and the pre-amp board twice.
All is good. I have started measuring the idle current and it was going up slowly(which is good). Around 5mV, suddenly it was dropping toward 0, and it reached 0.
I have took everything apart, and measured everything again. I did not find, anything wrong. I put it back together and this time, the idle current started going up way to fast to my liking and of course, it started smoking at the center channel pre-amp board. I have turned it right off, to don't cause bigger damage.
Found a 2.2 Ohm resistor(R6292) near the connector(emitter resistor for the TTA transistor-Q6102), with very high resistance. I have replaced it, could not find anything else wrong.
I have tried it again, after inspecting everything again. Still smokes.
I would need help, tracing down why it keeps smoking.
I have also replaced C6022/50V(capacitor between the two TTA/TTC transistors, just in case). I have to recognize, that I did not replace TTC, because it wasn't blown(initial repair), only the TTA.
In these amps, almost every time, blow the same components.
Capacitor has the right orientation, I have checked.
I would appreciate any help.
Tibor
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