68kMLA Classic Interface

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Classic II, vertical collapse, no 12.6v out of flyback.

Posted by: emuboy on 2024-04-11 10:10:02 I spent the last 2 days recapping and cleaning this Classic II, 220v, and I'm extremely unappy to discover that I have nothing out of Pin 2 of the flyback transformer, there is no 12.6v output to the pin 2 of the TEA2037, everything boot and I have a bright horizontal line on the screen,event the NMI does sounds, I just spent the entire day recapping the AB after recapping the LB and my heart it's broken. I can't seem to find any flyback transforer, so, I have been thinking, if a +12.6 it's everything I need, can I cut RL2 (spoiler, I already did to check for shorts) and feed a regulated 12.6? how bad would it be?

Posted by: Callan on 2024-04-11 12:14:48 Can't do that. That's a center tap and it's feeding both sides of the outputs. If your looking for a transformer you'd be better off buying this... Macintosh Classic II (M1450)Analog Power Board 630-0525 parts repair | eBay <p>non working for parts looks good </p> tinyurl.com

Posted by: Callan on 2024-04-11 12:20:09 That or I'd pull the transformer and verify it's bad with an lopt tester. They used to sell a cheap kit you could build (dick smith)

Posted by: emuboy on 2024-04-11 12:50:02 Sadly I'm in the UK and macs of that age don't come up that easily...

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