Hafler dh 200, bias setting issues.

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Hi Kansas1973 - Sorry about your brother... So let's get this amp up and running. To check whether the MOSFETs are toast do this:
1) Remove them from their heat sinks
2) Then with a voltmeter set to test for conductivity (the setting with a diode and a note typically)
3) Then use the meter to charge the gates.
I have written up a 5 step test process (attached)
These are rugged MOSFETs however, so do not dismiss them before you test all 8.
 

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jwilhelm: There is no protection circuit on a Hafler 200 - only an output fuse. Even if that was blown, Kansas1973 should still have 240mA BIAS.

My guess is that there is something amiss with the driver board. Diodes reversed by chance?
 
R-39 resistors were bad on bot boards, had a couple of transistors that the soldering was a little shotty..
I've been listening to some Black Sabbath for couple hours now and it sounds great!
I want to say thanks for all the comments, I've learned a lot and appreciate everyone's time..
 
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