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N Cook
 
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Default 300W PC power supply, no POST beep, smell, smoke, bang,dead

Jou Jye 300AP
Blown 5 amp mains fuse
There is a 1/2W resistor between the common point of the 2 x 200V mains side
electrolytics
and one of the 2 leads , high V side of the large isolation transformer,
marked on pcb as R5 now reading 98 ohms
Overheated and probably had a brown and a red band somewhere in the value.
Covered with some 125 degree shrink-sleeve that has charred. This was to
protect against touching other parts but this R was on end and lead doubled
back and presumably the bang was the long lead shorted to the other barrel
end of the R as severe tell-tale smoke 'jet-trails' at that point, no
ceramic spacer or anything .

Anyone hazard a guess what the original value might be. ?
The 2 main 2SC2625 and 200V electrolytics seem OK.

Parallel to the 4 wires of the mains side bridge rectifier is a small
sub-circuit
with (2S?) K2645 and a L8561 8 pin IC, is this all a crow-bar circuit to
knock out the mains fuse?

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