US Amps USA400

This amp uses 75344p (TO220) fets for the power supply. All fets are shorted and all gate resistors are burned to a crisp.

None of my trusted vendors have the 75344's in stock so I'd like to confirm that the IRF3205 would make a good substitute. It appears to be a perfect match!

Lastly, I'd like input on a good value to use for the gate resistors.

Thanks!
 
you never wanna work on a vlx 400
and i heard theres alot of special must know's and only the us amp parts work anything else just blows it
only a few ppl are qualified and not many more know enoff to do it right

Not in my experience. USAmps used some of the most common parts available with the exception of their SAT (just a PICMicro). Then again, if you're not experienced I would never recommend repairing any amplifier with that much power capability. A current limited power supply is a must. At that power level, I would power up the audio stage and power supply stages separately to ensure everything was correct outside the heatsink.
 
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