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I've got a old Mortima that's running waaaay fast even after I serviced it, but I don't actually have a demagnetizer. What I do have though is an old CRT computer monitor with a degauss button on it.

Has anyone ever tried to demagnetize a watch by holding a watch to the front of an old fashioned CRT and hitting the degauss button? The internet says it works, but well... the internet says a lot of things and my CRT is heavy and on a high shelf in my basement. If I don't have to pull it down I'd rather not.
 

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Take the cover off and hold it up to the deflection yoke. You'll be lucky if it doesn't jump outta your hand.


Don't do that, it's dangerous in more ways than one. I've never tried it but in order to do anything, the demagnetizers field has to be greater then the magnetization field plus the hysteresis. I do know of an example.....

Well let me tell you a funny story. I've put it up before so maybe it's boring to some. When I was in college, I went to the Exploratorium in SF; an amazing showcase of science and physics. One display had a color TV with a dot-bar generator set on white and a horseshoe magnet. You hold the horseshoe magnet up to the screen and the electrons are deflected around the mask so they hit the dots differently. The result is neat color patterns around the magnet; obstensively showing you magnetism.

So a while later, a friend who had graduated before me and got a real job (/envy/) bought a big color TV, I mean over 30". So I was telling him about this exhibit in the Exploratorium and he gets a horseshoe magnet out and tries it. Low and behold, when the magnet is withdrawn, the pattern remains. Bam, just ruined a several thousand dollar TV. All the turning it on an off didn't do a thing (the degausser runs when you switch it on).

We were able to restore it by going over it with a tape head degausser, much to his relief.

The point to all these keystrokes (besides entertainment) is that the degaussing coil in a TV (and it surrounds the screen) it only strong enough to correct the magnetism in the screen mask (made of Invar, similar metallurgy to a hairspring) that is caused by the earth's magnetic field, which is pretty weak.

To accomplish your goal, you need anything that has an A/C coil that isn't magnetically shielded (transformers are pretty well shielded). One good suggestion is a Weller Soldering Gun, but they are the price of a decent degausser. Don't expect the $10 Chinese buzz box to work, some say it does but they really need to be closer to the hairspring to be completely effective.
 
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