68kMLA Classic Interface

This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.

Click here to select a new forum.

iMac G3 help

Posted by: TheRetroMacNerd on 2016-09-26 15:19:23 So my iMac G3 DV Graphite that I rescued from a trash heap makes a whirring noise when turned on, then the light goes green, then it shuts off after a second. My other iMac G3 (Bondi Blue Revision A) just makes a humming noise when it gets plugged in and no power light, nothing shows up on the screen, nothing. Does any body know what's wrong with these 2 beauties?

Posted by: Bunsen on 2016-09-29 08:54:12 Moved to correct forum.

Posted by: goncalo on 2016-10-03 16:41:38 Hi I also have this buzzing in all my iMac G3s TL when on stan-by. It is coming from the Power Supply board and it starts as soon as I plug it to the mains. Something is vibrating and emitting a high pitch sound that is hard to pinpoint even with the board uncovered. Maybe a thermal scan could help locate the culprit, I dunno. Unfortunately, while I have just reassemble one Rev. B, I took no pictures of the board's components. But I have scanned the reverse of the PS board. Would love to ear from the electronics wizards in da house.

Posted by: goncalo on 2016-10-03 16:54:50 Another fun fact I have come to know about these iMacs. Sometimes, after some random operation, it stops working and it just there, buzzing. You press the power button and it just makes a different buzz while you are pressing it. You lay it to rest unconnected and in the following day everything is OK - like if it never happened... 😛 What can I say, I just love these colorful, child-like contraptions 🙂

Posted by: goncalo on 2016-10-04 08:16:20 Could this be the phenomenon known as “Coil Whine” or “Coil Squeal”? https://en.wikipedia.org/wiki/Coil_noise http://www.ukgamingcomputers.co.uk/capacitor-squeal-coil-whine-explained-a-63.html I’ll try to get some hot glue over the inductor(s) and see if it dampens the noise.

1