today i'm going to look into fixing my NEC MultiSync. this is the original version, the JC-1401P3A. 
yesterday it blew the main AC line fuse, and i suspect the degaussing circuit.
i've rigged up a 100 watt light bulb to limit the current so i can test the coil separately from the monitor
yep, the coil seems fine
the power supply just slides out.
I'm interested in this odd-looking part, PTH451C.
inside there are two disks and some spring contacts
the disks are made from a material with a positive temperature coefficient. as it heats up, the resistance increases.
the idea is that the degaussing coil gets a high current, then the PTC heats up, increases in resistance, and then shuts off most of the current to the coil.
that third terminal goes to the other resistive disk which heats up the first one so that the holding current is less (should be only a few mA).
made some measurements and it looks ok. 🤔
you can tell it definitely gets warm during normal operation. check out the discolored PCB!
while I have it open I might as well fix a few cracks. this is bent, too, but a heat gun will soften it and I can reshape it with my fingers
trying out the baking soda and super glue trick
after a little sanding it's basically done. I'm not going to be able to reproduce the surface texture but this is all underneath so who cares
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