Mac SE/30 Display Suddenly Wonky

[powellb]

Over the weekend, I left the Mac SE/30 running for #Marchintosh, but came to it this morning and the built-in monitor has gone completely strange. First, I could only see a picture when turning the front (and interior) brightness settings to max for both; whereas, it used to be normally adjusted. However, the display itself is now stretched ridiculously large in the horizontal and less so in the vertical. I have attached a picture of what it looks like now. Adjusting the pots on the logic board shows little to no change on the display.

I recapped and reflowed the analog board 18 months ago. I recapped the logic board before that. I also put in a Babyface power supply a year ago (my original Sony PSU is recapped and fine also).

I thought maybe the CRT gave up the ghost, so I swapped in another Samsung CRT I had from a scrapped Classic. It is behaving the exact same, so it isn't the CRT. I inspected the analog board and could not find any issue (flyback transformer isn't cracked and the main bar is solid). I typically use a video card from zigzagjoe as my main display, and that is working just fine. It is only the internal display.

Any ideas on what could have gone wrong? A failure somewhere on the analog board I am assuming, but I don't have the expertise to independently figure out the diagnosis of the CRT signaling.

 

[powellb]

I have been working trying to figure this out, and it seems that something is amiss with the "width" control circuit. The width adjustment is a coil within a plastic tube. When I put a metal hex driver in there to turn it, the screen width gets much smaller, and I can adjust it. However, once I remove the small hex driver, it immediately reverts to the image above. Additionally, the hex driver is far too hot to touch.

I recall reading years ago of people using small metal objects in there to correct it, but I would like to know what the issue/correction is. I imagine that component is now unobtanium (other than recover from other boards).

Any ideas on the width control circuit? The capacitors connected were all replaced as per above during the recapping.