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yaffle2345 · **Posted:** 19 Mar 2019, 00:07

I'm having a similar problem with my 909 - it's completely dead.

I should say I don't know much about electronics, but I do have a multimeter - how difficult can it be? :-)

The board's a VWR1287 and all the fuses (7 little ones and the big one) seem fine.

On the outputs:

CN202 has +14V on pin 2, +5V on 10 and -27V on 14. But the +5V on 4 and the +3.3V on 7 and 8 all seem to be 0V
CN203 has -14V & +14V on 2 & 3, but the +5V & -5V on 6, 7, 8, & 9 are all 0V.

There seems to be a little darkening on the board around resistors R105, R106 & R109, as if they've been very hot, although they don't show as being open-circuit (although I don't know if that can be said for certain while they're on the board).

If anyone has any advice on the best way to proceed, it would be much appreciated :-)

The post above mentions checking Q101, what's the best way to check a voltage regulator, do I have to test the voltages with the power supply connected? What voltages should I expect to see there?