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Old 01-12-2013, 02:54 AM
stuartjohn24 stuartjohn24 is offline
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Location: Chippenham, Wiltshire, UK
 
Join Date: May 2011
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Thanks PAPER,

I have cleaned the board up but no luck as yet. One of the processors is not kicking the watchdog so it keeps resetting.

The reason for this is either a duff processor or a fault elsewhere on the board. There is a MOSFET on the amplifier card that's getting very hot, (in my first pic of the PCB its the one on the lower left in the corner) it looks like its controlled by the processor card and is used to power the amplifier up once the processor card has been woken up by the MOST bus.

I'm guessing there is a fault elsewhere with either of the amplifier ICs that's drawing excessive current. Examination with a thermal camera has yet to determine anything.

Pretty gutted really, seems I've been really unlucky and got a much more serious problem. It won't be as simple as replacing caps and amplifiers as I had hoped!

Stuart

Last edited by stuartjohn24; 01-12-2013 at 02:57 AM.
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