Why does my replacement FET (FB31N20D) keeps failing wherever in the output bank I place it? Are they not genuine? I'm not seeing any other problems but even at a low level they short and the amp goes in protection.
Like Tim said you may have a driver transistor that is defective on audio driverboard or may even have a shorted Inductor..
I would start with checking the MPSA56's And MPSA92's on the driverboard to see if any are shorted or leaking..
Also if you unsolder the driverboard from the main board hold it up to a light and look thru the board do you see any dark spots?
I would start with checking the MPSA56's And MPSA92's on the driverboard to see if any are shorted or leaking..
Also if you unsolder the driverboard from the main board hold it up to a light and look thru the board do you see any dark spots?
Well I would have to check that driver board but I think that's the last thing I wanna do, as what I'm saying is its just the one FET that keep failing whichever position I place it. The original ones doesn't short its just the replacement at all times.
So would that be a driver board problem?
So would that be a driver board problem?
Not the gate resistors Tim, they all are OK all 47 ohms parralel with diodes that checked off OK also. As I mentioned its just one FET is failing and I've put it in all the position where the originals I shift around and it still failed after replaced.
I suspects inferior and cheap replacement but just need other opinion to confirm, or if there is a different fet that is more withstanding that can replace the FB31N20D an upgrade or something.
Merlington I don't know the history behind the source, all I can say is I bought them where I'm living and its the Caribbean, guess they are imported from elsewhere.
I suspects inferior and cheap replacement but just need other opinion to confirm, or if there is a different fet that is more withstanding that can replace the FB31N20D an upgrade or something.
Merlington I don't know the history behind the source, all I can say is I bought them where I'm living and its the Caribbean, guess they are imported from elsewhere.
it should be directly connected to one of the driver transistors use ohm or follow the trace to the driver card.
No Perry, just one each time and always the replacement, even when I shift it to another position where I trade place with original it just blow (not destroying the physical package but short zero ohm on all legs).
Also be advised that it plays for a few minutes and give out even at low audio levels.
Also be advised that it plays for a few minutes and give out even at low audio levels.
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