They were tightly clamped. I just measured the roughly 20v between pin 5 and 8. After that slip It didnt stay powered on long enough before fuse blew to get any measurements.
I did. One seems to have failed dead short between all three legs and one seems to have failed completely open as I get no reading between any legs.
Reinstall it. Put the other one under the clamp so you can clamp the good one tight.
Do the two optos read the same or is there a difference?
Do the two optos read the same or is there a difference?
I did reinstall all those fets and the octocoupler seems to have survived via diode and resistance test.
I installed a inline 10 amp fuse. Right as I touch the + wire up even before the remote wire I can hear a weird sound emitting from it. The fuse didn't blow but the sound prompted me to quickly remove power wire.
In that few seconds it seem maybe th32 was warming up. The heatsinks is a couple degrees warmer there and the outputs are not clamped. The sound was like a sizzling sound. Th32 tests the same way as th320 wich appears to be the same part.
After a little while that part of the heat sink is still a couple degrees warmer . I may be just from the light on my bench or some other anomaly. So I dont think that component was warming up.
After a little while that part of the heat sink is still a couple degrees warmer . I may be just from the light on my bench or some other anomaly. So I dont think that component was warming up.
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I still have that cap jumped to keep the output fets out of circuit. Th32 is the bias spreader or whatever you would call it in this amp. It gets clamped down with the output transistors on the heatsink.
I dont think it is heating up. I think the light on my bench or somthing is causing that part of the heatsink to be a couple degrees warmer.
I didnt let the power wire sit on ther long because of the sound it was emitting. I didnt even get a chance to hook up the remote wire. My battery voltage was sitting right at 12v. I'm not sure if that's low enough to cause the amplifier to make that noise or not. I'm not used to amplifiers making noise unless I'm running it hard into load resistors with a 1khz test tone. I know some of these class d amps make a whining sound but it is nerve racking to me ahah. Should I just let it make the noise and see what happens? It didnt pop the 10 amp round fuse so it couldn't have been drawing a ton of current.
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