68kMLA Classic Interface

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Mac Classic II display issues

Posted by: covar7 on 2020-07-11 11:16:17 So I recently purchased a Mac Classic II that needed some repairs done. I got it up and running, but after about 10 minutes the screen went to max brightness and I could see lines running through the screen. Now I know it's not covered in the dead mac scrolls, but I did find the issue on page 52 (Including a screenshot of the issue). What complicates this is that I heard a loud hiss and smelled burning plastic as well and immediately turned off the Mac and unplugged it and removed the analog board. I'll include a picture of that as well. It looks like one of the pots shorted out and I'm not sure if this was the root cause or if this is a symptom of the aforementioned resistor going bad. Any tips moving forward would be greatly appreciated as I'm pretty new to this and don't want to cause any more damage.

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