68kMLA Classic Interface

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Power supply issues (Mac SE/30)
Posted by: Abeloos on 2025-03-17 11:49:17 Recently got a Mac SE/30 and as with my other vintage Macs, I recapped the analog and logic boards. Also added a ROM-inator II and 64MB extra memory. The Mac worked during testing until I reassembled it and closed the case. When switching on the power, the chime only came through halfway, the fan started spinning and then stopped immediately. Nothing else happened. This worked twice and then nothing happened anymore. Given that the PSU was not recapped yet, I immediately thought in that direction, given that the glass fuse is in good condition. For this recap I used the YT video of JDW with his corresponding list of capacitors at Mouser. However, after this recap I still have no output: no 5V, no +12V, no -12V, literally nothing! Someone here who can help me further to tackle the cause of this problem. And where could I get the electrical diagrams of this Sony CR-44M? Thanks in advance for the help.
Posted by: s_pupp on 2025-03-17 14:01:15 Click to download a pdf from www.macdat.net. The pdf is for CR-44. I do not know if the CR-44M is the same unit or not. I wish I could be of more help.
Posted by: jmacz on 2025-03-17 15:30:43 There's more knowledgeable folks on the SE/30 PSU that hopefully can help, but in the meantime it might help to clarify where you are measuring the voltages leading you to believe there's no output. Is that at the 10 pin connector coming out of the PSU, or on the analog board, or on the logic board? Also, if you have the PSU already opened and you're fumbling around in there, were you able to check whether the primary side and secondary side of the transformer is seeing any power?
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