68kMLA Classic Interface

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Mac Plus PSU showing 25v AC on Pin 6
Posted by: GoldTek on 2024-03-25 19:43:32
HI there folks, my first post here. I am trying to track down issues with a derelict MacPlus, in what seems to be a power supply issue. It was making the flup flup noise quite strongly, now is only making a slight tick sound to the same rhythm. Checking pin six (blue wire) on the cable from the PSU to the mobo shows 25vac, where as i understand it this should be the 5v DC line... Any pointers would be appreciated!
Posted by: GoldTek on 2024-03-25 19:46:38
I should also say that rotating R56 all the way counter clockwise makes no effect on this voltage.
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