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Dead CS80 - finding a short

2017-02-14 by pyjamagroove@...

So my beloved CS80 died on me after calibration and tuning.

To resume:

1. After calibrating BA, KAS and M-boards, 4th M Board 1-channel did not play funky3, memory 1,3 and panel presets (last 4).

2. After inspecting BA board for the possible cause of this the PSU died (played a low note for the few seconds first).

3.Rebuild and calibrated PSU - Died again after power on (also low note first).

4. The upper GND and lower 15V rails are shorted!

5. I´ve tried to find a short isolating -6,5 and 8,5V terminals on the KAS, S/H, KBC 1 and 2 boards - no success (desoldered the wires and the ground and checked with my DVM for continuity - there were no shorts).


I am out of ideas. If the rails for GND and 15v are shorted does that mean that I should repeat the point 5 but between +15v and E terminals on every possible board? Seems logical.

I would appreciate any help.


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