Need help with Rockford Fosgate 801s

[robsmetalcraft]

I have an 801s I bought used and got burned on. Anyway ,amp powers up, than in less then a minute blow the fuse. I pulled cover and found no signs of obvious damage , checked mosfets impedance across outer pins and all measure in the mega ohm range with same readings for the similar ICs. Since I can't keep it running long enough to trouble shoot (I also tried powering up unit without input or output connections and had same results). Next I tried starting it up with larger circuit break hoping problem area will show itself by either blowing itself up or at least heating up enough so I can locate problem area with heat gun. Still nothing, heat at transformer and mosfets but pretty even .This last test was done without input or output connections. I'm just getting into electronics but some knowledge and equipment ,DMM, dual track Fluke scope. Any help would be greatly appreciated. Thanks.Rob

[nigelwright7557]

You could try breaking it down.
Check power supply on its own is not blowing the fuses.

Look for DC on the speaker output.

Thats a start that might give a clue or two.

[robsmetalcraft]

So isolate power supply?

[robsmetalcraft]

Just looked a schematic which isn't to clear, Not going to be easy to isolate. I 'am worried that it's the transformer ? I tried uploading schematics.File to big, sorry. I can email if someone wants it?