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Macintosh IIsi Power Supply Diodes

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Hi all, been a while since I last posted here, about the same time I tried to use my IIsi(s)...


so dug them out but neither of them would power on.


I would get a brief click, fan and light then they would power off again.


Tried replacing the fuses, which might have done more harm than good since the guy sold me slow fuses by mistake which I stupidly tested anyway.


after getting the right fuses they blew straight away.


so did some continuity testing and found at least a couple of the zener diodes are allowing current in both directions, but there’s no way I know of to know their values.


Wondering if anyone would happen to know what diodes are used at D302 and D305? See attached photo.


Thanks in advance!


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