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Macintosh Performa PSU wrong voltage

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I recently bought a Performa 450 which was in very good condition, no visible leakages, blown-up batteries etc. When I power it on, I can only hear a clicking sound from the speaker. Fan is working correctly. I measured output of the PSU and so far it looks like I'm getting wrong voltage on +12V and +5V lines. It fluctuates around +8.5V and +2.8V respectively. -5V line shows correct voltage though. Do I have faulty voltage regulators or should I recap the PSU? It's one of the Dyna Comp (not TDK). Close-up photos attached.

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Hi

If you had faulty voltage regulators, you'd most likely have nothing at all on the 5V or the 12V rails. 
As ever with those old machines, caps fail. Even if they're not swollen it doesn't mean they're fine. Low voltage typically suggests weak caps, so recap first and if it still doesn't work, then we'll have to do some troubleshooting...

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Thanks for the suggestion. I desoldered all caps in the DC voltage section and here's a complete list of values - maybe someone gonna find it useful:

  • C15 - 330uF / 35V
  • C16 - 82uF / 35V
  • C18 - 2200uF / 10V
  • C19 - 1000uF / 10V
  • C20 - 1000uF / 10V
  • C21 - 82uF / 35V
  • C22 - 82uF / 35V

All caps are rated at 105 degrees centigrade. Manufacturer is NIPPON, series LXF, which is discontinued. They recommend LXY capacitors as replacement, as they're low impedance and long life-type caps. Unfortunately, I can't find a supplier of those in my country, so I guess ebay is my go to place for now.

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