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In an SE that I have, the same symptom was caused by a short on the CRT neck board, capacitor C5. It's worth testing with a multimeter. Does the PSU short if the analog board is plugged in, but not the motherboard? Could the short be electrolytic fluid on the motherboard?

There are at least three different power supplies - by Astec, Apple, and Sony. I have the doc for the Sony CR-44:

Oh man, if only I had known when you shipped the PSU! But I thought for sure the issue would end up being in the ASC/capacitor area. An issue it is now having is rather bizarre - you kind of need a picture to see it: This SE/30: My working Classic II: Closeup of the dim "eroded" pixels...

I worked on the power supply for a while, but couldn't find anything useful without an oscilloscope. Something is wrong in the area of the switching circuitry. So I'll put off that for now. I got a spare PSU from CC, though its not the Sony one, so it wouldn't help me understand the one I have...

So if I try to measure the switching transistor output with the AC setting, I'll probably get nothing (or perhaps 0.9v?) whether it's working or not? That would be too bad. I went back as far as D252 on the 12v rail and D251 on the 5v - thats immediately after T151, in the hopes that I would...

Just an update - I've been looking at the schematic and tested up to the main voltage from the biggest filtering cap and subsequent inductor, its about 164v, which seems good. Voltage on the yellow wire - +12v - starts at about 0.9 and slowly and steadily drops when measuring, it got to 0.22v...

Some whine louder than others, so I do think it would be a good thing if we found a way to reduce the noise. I don't know much about electromagnetic frequency stuff though, all I know is that I've heard the frequency of the horizontal overlaps with the human audible range somehow. 

Oh, does it work better than before? That's great to hear! Impressive job on the hinges! I have many laptops with damaged hinges, but I've never tried a proper repair. Once there was a conspicuously lacking metal bracket - there never was one there but there clearly was space for one - so I cut...

Heh, I grew up with the sound, even though I'm only in my 20s - we were not rich growing up, and had a 32-inch CRT TV. Since then I've always had CRT monitors for my vintage computers, and most of them make that high pitched whine. For some reason even though my hearing is poor I can still...

Wow, I'm glad this was once made, I never knew. I'd like a SCSI to IDE adapter, but that's because I like the sound of a spinning hard drive rather than an SD card.

Wow, that site is super cool! I tried it with my phone, it did nothing. Then I tried it with my laptop and it worked at first but then after about 10 seconds says "chksum error" every time. I recorded the output of the laptop through it's input and it sounded fine to me, so perhaps there is...

I do indeed have a IIe Enhanced. I've encountered few disks that run on the IIgs but not the IIe - that appear to be actually coded for the IIe - but one is Arkanoid. It worked great on the IIgs, but on the IIe the disk just spun forever and the screen displays "Apple IIe". Perhaps someone can...

Yes, at least thats what the disks I'm using say: If I transfer the image of ADTPro, it always boots with no problem. But for examples, I have not been able to run images of Galaxian, Tetris, or Dig Dug (which it seems to me, as someone totally unfamiliar with the matter, could be due to copy...

I've had a horrible time trying to get disk images from the internet to my Apple IIe. What I do is download the .dsk, .po, or .do file, boot my IIgs into ADTPro from 5.25" FDD, transfer it via serial to the IIgs and have ADTPro write the image, and then attempt to run it. Some games will run on...

If you happen to have the Sony CR-44 one I think I would like one, so I can trade components and try to understand it in absence of an oscilloscope, unless you think that's a bad idea. I really am trying to understand power supplies by googling, but it's been difficult.  I should mention though...

I finally got all the capacitors in (except the three largest) and immediately replaced them all. That had no effect. :( I made a separate topic for discussing the PSU repair. If I could just get it running I'd be well on my way to having it running.

I replaced all the radial caps in my SE/30 PSU except the three largest, but it still doesn't work. I measured the voltages with my multimeter, with the negative probe on the black wires and the positive on the red/yellow/orange ones, and the voltages I got ranged from about a half volt to about...

All SMD capacitors in Macintoshes are 16v 47uF :)  

Well, what was the issue? 

"video unavailable" The mechanism is quite simple in these drives so a video would definitely help understand whats going on. I once had a drive that was stuck like a rock, but it was the larger, heavier 400k drive, I would not expect the same failure out of an 800k. Still, the procedure I used...