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Home Forums 68kMLA Macintosh Classic PSU problems — #1
Post #1 by quantumii
Source Forum68kMLA
CategoryHardware
Post DateSat, 29 May 2010 - 19:13
Original URLhttps://68kmla.org/bb/threads/macintosh-classic-psu-problems.20668/
Post
Hi,

A while ago I got hold of a nice little Macintosh Classic. It works, but the internal HDD does not spin up when connected to the internal PSU (It spins but stops), and the monitor has a shaky picture, and with every mouse click the screen contracts a little. Same for floppy reads (even more) and sound output :(

I connected a scope to the +12v and +5v lines on the HDD power supply cable, and sure enough, the voltage fluctates quite a lot, and you can see it sag in unison with the monitor wavyness and the floppy reads etc..

Question is, where to look first? Any specific caps I should replace :?:

Thanks

mp.ls