magnet on tv screen

Unless it was a really powerful manget, should clear up in a few days or after a few power cycles (on 5 minutes, off 15 minutes, repeat). The degauser will do its job.

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Leave it be. It will fix itself.

You can build a degausser. Wrap an iron rod with wire. Then run an ac current through it and wave it over the magnatized area on the screen.

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If the mask in the CRT is not damaged, this will probably clear in a number of days, from the degasser cycling every time the set is powered off and on again.

The other way to clear this, is to have a hand held CRT degaussing coil, and demagnetize the screen.

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JANA _____

i might be on a loser here but does anybody know if you can fix a tv screen after a magnet has been held against it(my 4 year old daughter) it is a sony 28" crt widescreen tv. there is discolour in one corner where the magnet has actually touched the screen. if not the tv is a rental anyway so i will have to return it a play dumb about the problem. any help would be great thanks

-- david wilson

There should be no need to do this. The internal degausser should clear it up in a few days or sooner.

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If it doesn't clear up on its own ( I have known this happen with computer monitors ) the use of a hand-held degausser would fix it ( eg by a repair chap ).

Certainly nothing serious to worry about.

Graham

That's a good way to warp the shadow mask. You want the alternating magnetic field spread out over a larger area. I made 14" diameter coils with 250 turns of 17 AWG double enamel with a double cotton covered wire. I made a coil winder and wound a bunch of them in 1970. I also used a heavy duty push button switch and a 20 foot AC cord so it was easier to find an outlet to use it on service calls. I still have the first one I built.

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Try unplugging the TV overnight. After about 30mins most TVs will automatically Degauss when reconnected. Standby is not enough. Might need a few attempts.

Wilfred

david wils> i might be on a loser here but does anybody know if you can fix a tv

And if that doesn't shift the coloured spot, you can use the magnet again to neutralize the magnetization. Simply pass the magnet over the discolouration with a semi-circular/wiping motion at 1 centimeter from the screen at the closest point, making sure the magnet always travels over the spot in the same direction, and with the same orientation (North/South). If the discolouration gets worse instead of better, flip the magnet over, so the opposite pole points to the screen. If all goes well, most of the discolouration should be gone after about half a dozen passes. The degaussing function (as described by Wilfred) should get rid of whatever is left.

Richard Rasker

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You should refrain from giving advice you've never tried. The degaussing coil of a TV isn't strong enough to undo the damage from a hand magnet. Maybe if you unplug the set and plug it in again forty or fifty times, it might start to erase the magnetized spot.

You need something with a stronger AC field. Back in the days of tape cassettes, bulk tape erases worked well. A largish AC adapter (stuck into an extension cord for portability) might generate enough of a field. Maybe a AC powered shaver would have a strong enough field?

Also: step back slowly while waving the magnet around. I've successfully removed magnetized spots with that technique.

Hi...

In the absence of a degausser or bulk eraser, a soldering gun will do the job, albeit slowly.

Take care.

Ken

Yes, Perhaps I should declare my only experience with this subject is with a speaker I put too close to the TV. What I suggested did work for me. A hand magnet on the screen might be an entirely different story.

Still , my suggestion wouldn't have done any harm either, and it "might" have worked.

Wilfred

VHS tape eraser.

I have a tape head demagnetiser that's good for this.

Graham

You appear to have forgotten your own advice. transformers dont produce enough field, nor do shavers or motors, I've tried both on floppy discs, with no effect. A shadowmask is a distance away from the front of the screen, so will see even less field strength. Once you see a bulk eraser you'll see why motors etc wont do it.

NT

You appear to have forgotten your own advice. transformers dont produce enough field, nor do shavers or motors, I've tried both on floppy discs, with no effect. A shadowmask is a distance away from the front of the screen, so will see even less field strength. Once you see a bulk eraser you'll see why motors etc wont do it.

Tape head demagger also had no effect.

NT

I strongly disagree with the above.

While a bulk tape demagnetizer is probably the best thing to use, I have demagnetized many CRTs with an AC pencil sharpener and a pencil. These are generally readily available. Cheap pencil sharpeners seem to work best. I generally use a Boston one .

While several feet away, insert the pencil to start the sharpener. Bring it close the the CRT and move it around, then back away from it before removing the pencil. You will now have a demagnetized CRT and a short pencil! Don't use a pen!!!!

If you want to see the effect, keep the TV on while doing it...it won't hurt. You will see the magnetic field in action.

cv

lol, maybe I'll try one of those if ever needed.

NT