Macintosh Color Display giving up the ghost

[VMSZealot]

After years of faithful service (I bought it brand new), my Macintosh Color Display seems to be giving up the ghost.

The tube itself still produces a bright… Well. Image is probably the wrong word. Mess. And it's just about possible to determine that the Mac is doing something in the mess. But the image is pincushioned jumping around wildly. So I was wondering if this is symptomatic of failing capacitors, and whether this is a particular problem with these monitors. But…

…When I tried to get a picture of the problem today, the image was as sharp and clear as when my monitor was brand new, more than thirty years ago. So… Am I going mad? What preventative maintenance do these monitors need?

It should also be noted that I live in an old house in a small farming village, and the mains power isn't necessarily right where it should be. Could that be part of the problem? My normally reliable (and thoroughly recapped) LC475 took a few goes not to sad Mac on that day too - only my (also recapped) LCIII was entirely happy - at least when plugged into a Fujitsu LCD monitor.

 

[gsteemso]

It really depends on how far out of spec your mains power can get. Power supplies are designed to cope with input that might be slightly off the nominal values for voltage and frequency, but get outside the range that something was made to handle and it becomes very unhappy. These days some computers have truly universal power supplies that will accept any AC voltage from Japanese 100V to European 230V (though I'll admit I'm not sure how well they would cope with something weird like 180V), and they don't care whether it's 50 or 60 Hz. Older stuff like classic Macs is a very different story though. Too low a voltage and it will flicker and/or just stop working; too high a voltage and the results defy easy speculation, though what you described seems plausible.

 

[VMSZealot]

I don’t imagine we’ve ever gone above 220v. I think that the power sometimes drops to… well who knows, but it’s got to be pretty low when LEDs start fading and flickering. Last weekend, the lights seemed okay, but that proves nothing.