68kMLA Classic Interface

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ATX adapter weirdness
Posted by: dv- on 2024-11-05 19:54:19
Hi. So, I had a small batch of these made, using the coupons and stuff that pcbway offers new users, it was like $2 each for 10: https://www.bigmessowires.com/2023/09/27/atx-to-mac-10-pin-power-supply-adapter-kit/

I've assembled six of them so far, and they all work in my Quadra, but only one of the six works in my IIsi. Wondering what that might indicate? (It doesn't seem to be an intermittent thing - it's always the same adapter that works, and I've tried 2 different PSUs.)

I've triple-checked all the solder joints, and tried reversing the resistors and capacitor even though they shouldn't be polar? Any other ideas?
Posted by: cheesestraws on 2024-11-06 01:23:42
edit: ignore, I can't read
Posted by: dv- on 2024-11-24 15:24:21
I ended up replacing my IIsi PSU with the template board from Caymac Vintage, the “Power Up IIsi.”

Works great. I only had a 90w PicoATX to use with it (250w is suggested I guess) but it works fine and powers a nubus adapter with an FPU installed. So a big thank you to Caymac is in order.

Some day I'll try to figure out why these don't work with a IIsi but I guess the IIsi is known for being a little special. 🙂
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