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couple of general se/30 questions

Heres more of an update. Its had plenty of time to cool down...

Turned on the switch and started filming. Nothing happened so I stopped recording. Tried booting off a 6.0.5 disk, but it strangely got stuck at Welcome to Macintosh (PSU or disk issue? Could be related to the errors), and then the drive was quiet... Turned it off and back on again, no issues, booted to rom. Tried the disk, and it had files on it? Ive booted my portable off it, so I know its good. But then, it happened. The screen expanded and kind of shrunk down again. It did this a few more times within the next minute, and then was stable again. So Techknight, you're correct, it seems like a power supply issue. However, it does not seem to be a matter of "warming up" now... Unless it takes longer than a few minutes to warm up. Its an 80 degree room, so I dont think there is too much to warm.

Does this still seem like a transistor issue? Is there something else I should be looking at? Should I just swap the whole power supply?

DO NOTE: We are living in a very old house right now (Building a new one, so its temporary) that constantly trips breakers when the toaster and coffee maker are on at once, for example. There are NO GROUNDS in this house, which I did not know until recently. There are "fake" grounding 3 prongs. Can this be the root of the issues? No ground or bad electrical supply from the house? The lighting flickers when i turn on my modern computer. I can try bringing it to a friends house and see if the issue goes away. 

 
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[SIZE=1.4rem]FYI, "warm" in the context of electrical parts could be the difference between room temperature and, for example, [/SIZE][SIZE=1.4rem]140 degrees Fahrenheit. Whether room temperature is 50 or 80 degrees Fahrenheit only changes the amount of [/SIZE][SIZE=1.4rem]warmup time, not necessarily whether warmup will happen or not.[/SIZE]

Do you have a UPS on which you can test it, to make sure the voltage isn't fluctuating?

 
No I do not.

Is this something I could send the PSU to someone to test it? Or would it be better to buy another?

as of now there are the following issues.

Sometimes upon cold boot the screen will jitter

sometimes upon cold boot screen is fine

sometimes the screen will shrink and expand and stabilize after being on a few minutes

 some disk errors were present which techknight says could relate to bad power supply (could be totally unrelated)

stuck on welcome to Macintosh screen on my known good 6.0.5 disk (could be totally unrelated. Logic board good.)

Its either the analog board or video supply. When the screen expanded in all directions that tells me that it’s not just the vertical circuit. It kind of sounds like a fly back transformer going bad, however, there are no typical whining sounds or weird noises or any flickering. If those errors are persistent no matter the disk, in addition to these problems, then it points to the power supply. I’d like to get some more opinions on what should be done first before swapping out stuff. Does anyone here have a spare working and known good power supplying could buy or swap for?

 
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Just checked and I have a Sony power supply installed. These are considered the more reliable ones...

At this point, should I send out the original to be repaired/checked or look for a replacement? Will the replacement need to be recapped right away? Are there any modern ones that might work better?

 
Finally got the analog board out. I don't see anything that stands out as obvious.

Is there any chance this issue could be caused by bad and old house wiring as described above?
Y7EMora.jpg.b45e821efd00b4b3390b82fb8fc44f59.jpg


Edit: Possible progress. Found out this cap circled below has one leg loose. I don't really understand what's going on here, so if someone who has done recapping before could help, that would be great .

When I gently rock the capacitor, I can see the leg plus solder move back and forth. Ya know, why don't i post a video. Could be fine, just a trace that came off the board if that's possible? There's burned PCB around it, which tells me that there's  not a good connection and it's heating up. Please let me know if this could be the source of my problems! :)



View attachment Loose_cap.mp4
 
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Edit limits up.... Forgot to explain it better.

I can push on the capacitor, and the one leg (shown in the video), moves in and out through the hole, HOWEVER, it also moves the trace. So it's almost like the trace came off of the PCB. Should I be worried about this? Another photo of the burned area. Id resolder but dont want to burn up the remaining trace if its not needed.

20181221_181453.jpg

Edit

Took the chance and removed the solder. Appears that the trace is fine... Again, some advice would be great. Sould the trace be glued down and resoldered? Could it have caused my issues even though it was still soldered?

20181221_184459.jpg

 
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Resoldered trace/cap and glued it on. 

I found an AB/PSU combo from an SE displaying jailbars for sale. All SE boards are compatible with an SE/30? 

I do need this SE/30 for an event in January (For only a few minutes). Will an original sony PSU work okay until next month when I need it until I have the time to get it recapped?

This AB says 0206 B, while mine says 0206 C. 

board1.JPG

board2.JPG

 
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This is it! I dont know how I missed this other thread... 



Same exact horizontal lines!!! (as shown in one of my previous videos) Same video size twitching! Just mine hasn't progressed as far yet... Has the same time frame, either after booting or after warmed up, and it will go away on its on as well. Oddly this guy fixed it by recapping, but mine already has new caps. Must be a transistor or IC as Techknight said.

Ordered a replacement analog board and psu from ebay. Hopefully the new PSU will fix this... 

Update:
Took apart my recapped PSU and noticed something... Arent there no new 400V 620uf caps made...? Thought I read those were discontinued and people moved to 680uf? The big cap in mine appears to have a slight bulge, and is very dusty, its a 400V 620uf black "Nippon Chemi-Com". Others appear new. Am I looking at an original capacitor?

 
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Finally got my replacement AB and PSU today. Inspected the new psu, saw no obvious cap leakage. Unplugged the Ethernet card( no  need to stress the psu when I'm not using g it) , mounted my old analog board, plugged everything in and switched it on.

Mission success! (For now). I left it on for about 10 minutes (with how the other psu was, I would have known if it was bad by then). No issues that I could see. Nice, stable image, and more importantly, no errors when browsing around on the rom disk! Popped in a floppy to see how the psu handled a load, no wavy lines or anything.

I suppose the issue is solved. Hopefully it won't come back...

Thank you everyone for your help!

 
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