68kMLA Classic Interface

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Weird dotted lines on Macintosh 128k

Posted by: Retrogamer9876 on 2026-01-24 12:13:54 I just recently received an original 1984 Macintosh 128k. I turned it on to find this weird pattern on the screen with the floppy disk icon in the middle. I searched the internet and found nothing that looked like this. It also made a weird static noise instead of the normal boot chime. I’m just wondering if anyone has any ideas on what it’s going on? Or some insight on what to do next? Help would be very much appreciated, Thanks!

Posted by: Byrd on 2026-01-24 16:13:43 It's most likely failed RAM, is the analogue board recapped/check voltages

Posted by: Retrogamer9876 on 2026-01-24 20:45:05 Analogue board has not been recapped yet. I also haven’t had the chance to crack it open yet. It did get a 1 mb ram upgrade in 85-86. Still need to check voltages though.

Posted by: Byrd on 2026-01-24 23:23:54 The third-party RAM upgrades for early Macs were often precariously placed in sockets, with wiring going to random points so have a look inside and see - check wiring all in place and see if the RAM upgrade can be potentially be reseated and contacts cleaned. I'm currently restoring a couple of 128K with RAM boards sandwiched on top and neither are easy to remove. Often the stock Apple RAM has failed by now too aka "bit rot"

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