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Macintosh SE analog board clicking
Posted by: Yanisssch on 2023-01-22 10:39:44 Hi everyone, I’m currently fixing a dead Mac SE I received but still after replaced all the caps when I try to turn it on, there is a clicking sound from the Flyback transformer (I think) and no images, no sound but the Vent is turning properly, if anyone can help me? Here the video: View attachment IMG_0245.MOV on Reddit if you cannot see the video : https://www.reddit.com/r/VintageApple/comments/10imfc3 Thanks to everyone who can help me ^^
Posted by: mrojas36 on 2023-01-23 11:50:55 i went to use my Mac SE today and heard the exact same sound. Pulled the logic board, analog board, noticed some cap leakage from the power supply. The power supply was only putting out about 40% of the required voltage. The leaking caps caused corrosion in that corner of the power supply PCB. I removed the solder mask with a fiberglass pen to get to actual copper and inspect the trace damage. Fortunately no damage. I coated the exposed copper with some solder and now I await my new caps.
Posted by: Yanisssch on 2023-01-23 12:09:42 i went to use my Mac SE today and heard the exact same sound. Pulled the logic board, analog board, noticed some cap leakage from the power supply. The power supply was only putting out about 40% of the required voltage. The leaking caps caused corrosion in that corner of the power supply PCB. I removed the solder mask with a fiberglass pen to get to actual copper and inspect the trace damage. Fortunately no damage. I coated the exposed copper with some solder and now I await my new caps. View attachment 51530 I changed every caps I had it’s the same thing but I had the same leaks as yours But it’s not that much like you I think, I can’t measure the voltage out because my multimeter is dead and I need to take one when I got my pay 😅
Posted by: mrojas36 on 2023-01-23 12:21:09 Yes your corrosion is not as bad as mine. The multimeter will tell us a lot. Thanks for the picture. Can flip the power supply board over so I could see the top of it?
Posted by: Yanisssch on 2023-01-23 12:24:27 Yes your corrosion is not as bad as mine. The multimeter will tell us a lot. Thanks for the picture. Can flip the power supply board over so I could see the top of it? Yes of course here for you:
Posted by: mrojas36 on 2023-01-23 12:31:35 Thank you so much! You have the exact same power supply I do. And apparently the same issue. I stupidly started removing caps thinking I could just buy a recap pack. No schematics, no recap guide, not much on the internet. So I reverse engineered what cap goes where. This is what I came up with. I should have marked them down first. Do these values match your cap values in these locations? We will get our dead Mac SEs working!
Posted by: Yanisssch on 2023-01-23 12:58:55 Thank you so much! You have the exact same power supply I do. And apparently the same issue. I stupidly started removing caps thinking I could just buy a recap pack. No schematics, no recap guide, not much on the internet. So I reverse engineered what cap goes where. This is what I came up with. I should have marked them down first. Do these values match your cap values in these locations? We will get our dead Mac SEs working! View attachment 51544 Okay I checked it’s the same power supply! If you want you can add me on discord if you want to speak easier
Posted by: Yanisssch on 2023-01-23 12:59:53 Okay I checked it’s the same power supply! If you want you can add me on discord if you want to speak easier Sori#2821
Posted by: mrojas36 on 2023-01-23 18:35:36 So here is what the service manual says about our symptoms. Check Cable at J12. Power Supply. Analog Board. Logic Board. Like we have a lot of spare parts lying around. My bet is on the Power Supply. We get that working our machines will work.
Posted by: Yanisssch on 2023-01-24 17:20:31 So here is what the service manual says about our symptoms. Check Cable at J12. Power Supply. Analog Board. Logic Board. Like we have a lot of spare parts lying around. My bet is on the Power Supply. We get that working our machines will work. View attachment 51558 That’s pretty good thanks for the page, btw I tested the power supply with any new multimeter I got the right 12v and 5v but for the -12v I got -9v idk if it’s normal. Today (Paris time) I will receive the last caps I needed on the analog board (film cap 3.9v 450v it will replace the 3.9v 35v) and we will see if the Mac SE will revive, if not i need to think how can I fix xD, I will keep you informed during the day
Posted by: mrojas36 on 2023-01-25 19:50:56 Ok a received my caps and recapped the power supply. 5v rail is now good, 12v is now good, but -12v is low. When I power on same results. Ok so more issues. Since I want to add more mods to this Mac SE I am exploring doing the power supply upgrade. Other people have given up trying to keep these old supplies alive - especially these non-Sony supplies like you and I have. They remove the old circuit board from the supply, leaving the plug, switch, and case. They find a modern FlexATX PSU and pack that into the now gutted case. This gives you a much more reliable, more efficient supply in the same factor needed for a compact Mac.
Posted by: mrojas36 on 2023-01-26 16:01:45 Ok swapped my bad supply with a good supply and voila!
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