68kMLA Classic Interface

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Powering an Imac G3

Posted by: cuno on 2019-09-24 03:28:34 How would I go about directly powering an Imac G3? I recently found one of these on the street. It is a slot loading blue version. Motherboard: 820-1275-a. The crt and plastic where completely destroyed and taped together. So the first thing I did was safely removing the crt and taking out the analog board. That's when I realized this project might get tricky. The analog board was very dirty and in bad shape. The logic board, however, seemed completely fine. plugged it in (without the crt) and pressed the power button. A short beep came from the speakers and the light lit up, but nothing more. After some examination, I concluded that the logic board takes in AC from the analog board, which then goes to the attached down converter. So the question here is: How do I supply power directly to the logic board? I don't have a lot of knowledge about electricity, so I would really like some advice before doing something stupid 🙂

Posted by: bibilit on 2019-09-24 04:22:28 http://bylenga.ddns.net/index.php?page=vcr.php Can help

Posted by: cuno on 2019-09-24 05:37:10 Thank you for the link. I've been reading about these conversions and I might end up taking that route. However, I would really like to know if it is possible to just supply ac to the down converter just like the analog board would. It raises some questions. Why is it marked + and - if it's AC? Also, what voltage does the down converter expect?

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