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How to mod an ATX PSU for 10 Pin Macintosh (for example IIsi, IIci, Quadra 700 and others)
Posted by: Von on 2018-11-22 09:07:13 Success! While the above is not pretty, it finally worked. The layout is the same except that the transistor's pins did a 180. When I jump PR +5V_SB to the far side of the 10K attached to the center pin, the hard drive connected to the PS fired right up. I will try to get soldered up and tested in the IIsi soon. @superjer2000 I appreciate your guidance on this. To those on holiday today, Happy Thanksgiving!
Posted by: peska on 2020-11-14 02:57:57 I just replaced the fried PSU of my Performa 630 with a 200W HEC-200SA-2FX ATX. I used your inverter for the power on/off logic and it worked like a dream. I used a 3904 NPN. Just wanted to say thanks :ii:
Posted by: ironborn65 on 2021-01-10 02:22:05 Me too, just to say thank you all!! This is a very precious forum and thread The 220V AC to 12VDC is a 120W transformer for LED strips. The picoATX is 90W. In the original setting the PSU could turn the CRT as well. In my case it is collected directly to the 220C in (not shown in the photo) Since I do not use an external cards and an internal HD I believe the power provided is enough. The PN2222A is under the picoATX.
Posted by: Joe_Goes on 2023-05-14 12:27:01 Hi everyone, just wanted to say a big thank you to everyone on this thread specially @Von for the photos of his labelled PCB of the soft power. THANK YOU EVER SO MUCH GUYS 🙂 You saved my Quadra. Parts used 300W Seasonic SFX SFB Manufacturer code: SSP-300SFB PN2222A NPN Transistor 1K and 10K Resistors Small PCB
Posted by: Joe_Goes on 2024-02-01 12:10:33 Been a while but thought I’d share
Posted by: slomacuser on 2024-02-01 22:29:22 Very nice. I’ll buy it. 😁
Posted by: markgeek36 on 2025-11-29 09:14:21 Hi everyone, just wanted to say a big thank you to everyone on this thread specially @Von for the photos of his labelled PCB of the soft power. THANK YOU EVER SO MUCH GUYS 🙂 You saved my Quadra. Parts used 300W Seasonic SFX SFB Manufacturer code: SSP-300SFB PN2222A NPN Transistor 1K and 10K Resistors Small PCB how are you handling the soft power on?
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