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Holy crap! 350F is *WAY* too hot! When you bake out parts that have been exposed to moisture prior to reflow soldering, it's normally a few hours at just over 100C, or around 212F. Any hotter than that and you'll be wrecking things. Not to mention plastic outgasses all kinds of nasty substances...

You have to be careful. A lot of these travel converters are not transformers at all, but triac based circuits that work like a light dimmer with a fixed output. They are intended for purely resistive loads only and will usually fry electronics connected to them. Transformer based travel...

That could very well have been the same opto-coupler problem in the power supply that I saw on numerous PF series monitors. In those, the vertical output IC was the first to succumb to the over-voltage but it's entirely possible that a different monitor would blow the HOT instead. Most of the...

I think what is happening here is the power supply voltages are climbing up until it triggers the over-voltage crowbar which shuts down the supply and it repeats. Are there any more questionable solder joints on the analog board? I don't have one of these to look at, but I would look at the...

I'm betting you still have a bad connection somewhere. Look closely at the cable between the motherboard and the analog board and check the solder joints on both ends. Pushing in on the sides causing the problem to go away is a dead giveaway that there is a bad connection. Always best to take...

It was undoubtably expensive, but the color active matrix panels were even more expensive, requiring 3x as many pixels for the same resolution. I remember it was pretty much a given that an active matrix screen would have at least one dead/stuck pixel, usually 2 or 3. It was that or live with...

And if that doesn't work, desolder and remove the offending keyswitch, take it apart and clean it out. This is a fairly common occurrence on these.

Do you have access to an oscilloscope? Failing that, check the voltage levels between each CRT pin and ground. It's entirely possible for a heater to cathode or cathode to G1 short in the CRT to cause this symptom.

I don't think storage conditions have much to do with it, though heat does speed up chemical reactions, so warmer conditions may speed it up a bit. Honestly I'm surprised so many of these cells *don't* leak after so many years. It's remarkable that one could go 20+ years without leaking the...

With the lid on, I don't think you'd want to have the fan not running at all. You may be fine to put a resistor in series with the fan to slow it down a bit, reducing the noise but still keeping a bit of air moving. Otherwise leave the lid off and it'll be fine with no fan.

Well, I have a good vacuum pump, but the chamber is the difficult part. Suck the air out of something and you end up with intense pressure trying to crush it. I don't know how an LCD panel would behave in a vacuum though, it may leak/boil out the liquid crystal compound.

It happens. I once did a similar move as the OP here and whacked my hand against the neck board of a monochrome VGA monitor, cracking off the pip while trying to unplug something. Several years later I was working on a nice 15" SVGA back when that was considered quite a nice monitor and I left...

IDE was a simple hard disk interface, little more than an extension to the AT bus. SCSI was a multi-purpose peripheral bus. It was designed right from the start to be much more than a hard drive interface.

LOL that's kinda cute in its own way. I've also been dismayed at the lack of selection of small, reasonably high quality 4:3 LCDs. All the decent stuff is widescreen while all the retro stuff I'm into is 4:3.

DC can also cause electrolysis within the display, breaking down the conductive oxide electrodes. The fact that this occurs on the edges does make me suspect that moisture has something to do with it. It isn't something I've seen before though, and I'm not sure why it would work ok for a while...

If that were the case, why wouldn't they use the correct gender in the first place? Male DB-25 is a serial port in the PC world, although most were DB-9 by the Mac Portable era. I'm guessing that was a custom interface for whatever peripheral it came with. It would help greatly to see what's on...

Many of the capacitors serve as decoupling for various ICs on the board. When a logic line switches states, it is fighting parasitic capacitance of the PCB traces and whatever load that line is driving, as well as parasitic capacitance internal to the chips themselves. The effect is that the...

The video circuitry shares the system RAM to hold the bitmap of the display, so bad memory or the circuitry supporting it can definitely corrupt the video. I would first check carefully for bent/shorting pins on the bottom of the board, then start looking at the memory address decoding...

It could be debated that the choice was a sound business decision. In any product cycle there will be a push from marketing to add features, a push from the bean counters to cut cost, and a push from the engineer(s) to make their baby as great as possible. All sides have to pick their battles...

Watch out for that 330 VDC bus, the big bulk filter capacitor packs quite a wallop, it is arguably more dangerous than the EHT in a CRT monitor although most people seem to have a much greater fear for monitors. Switchmode power supplies deserve a healthy amount of respect.