Im working on a Mosconi 5/30 thats going into protect. The PS runs for about 3 seconds and then shuts off. Im finding the Class-D section, Ch5; may be the culprit. Sometimes I see drive signal on the gate of some of the fets - and this drive signal reveals the falling edge not operating correctly. Its like the pull-down transistor may not be operational as the drive slopes instead of squares down. Other times the drive signal just has straight DC on it.
If I probe CH5 output terminals; sometimes the amp will try and stay powered on at 1.2A draw but its not stable enough to keep testing.
The parts in this amp are a bit foreign to me. I took this amp in thinking and hoping one of the ClassAB channels were the culprit and that turned out to not be the case.
Any pointers?
Photo of the Class-D section coming just a moment
If I probe CH5 output terminals; sometimes the amp will try and stay powered on at 1.2A draw but its not stable enough to keep testing.
The parts in this amp are a bit foreign to me. I took this amp in thinking and hoping one of the ClassAB channels were the culprit and that turned out to not be the case.
Any pointers?
Photo of the Class-D section coming just a moment
I just tried that and no difference made. I found one of the 85n10A output transistors failed, but it probably failed on account of me fooling the amp to stay powered up. I dont have any 85n10A here right now. Whats a good sub for testing? I have some IRF3710.
I know nothing about this amp. Check the driver for the FET that failed.
Can you find a point to inject a signal so you could test without FETs?
You could try (just to get it working for testing):
3710
3710z
540
640
640n
3415
Can you find a point to inject a signal so you could test without FETs?
You could try (just to get it working for testing):
3710
3710z
540
640
640n
3415