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Permanent Magnets & TV screen

  1. Aug 1, 2003 #1

    If you hold a strong permanent
    magnet up to a T.V. screen while
    it is on, the magnetic field
    does some really intriguing
    warping of the image. When you
    take the magnet away the image
    goes back to normal except that
    the color is now patchy and in-
    consistant. This latter effect
    takes months to clear up.

    I used a very strong permanent
    magnet pried off of a speaker.

  2. jcsd
  3. Aug 3, 2003 #2
    Is this a question or an FYI? I have a giant speaker magnet and have done it with my TV, but there didn't seem to be any effect lasting more that a few seconds (after removal of magnet from vicinity). I don't see a warping of the image either, the image is just polarized or something so only one color gets through, depending on the strength, distance, and polarity of the magnet.
  4. Aug 3, 2003 #3

    Just an FYI. When I did it the
    image became all warped: parts
    of it would be squeezed into
    narrow bands leaving big holes
    with no image in them. It was

    Actually the first TV I tried it
    on recovered quickly with no after
    effects. The second TV acquired a
    disturbing patch of incorrect
    color where I'd held the magnet
    the longest.Hence the warning.

  5. Aug 3, 2003 #4
    The magnet alters the path of the charged electrons approaching the screen, so the colors don't go where they are supposed to. If the effect remains once the magnet has been removed, it means that part of the screen has remained magnetized. Usually, it can be deguassed using a special tool, which de-magnetizes the screen and returns things to normal.
  6. Aug 4, 2003 #5

    This is cool to do, even with a relatively weak magnet. My monitor has built-in degauss, so you should check if yours does before trying it. I think a lot of the newer ones do.
  7. Aug 5, 2003 #6


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    before they came up with degaussing and such, you could use a magnet to "pull" the distortion out of the screen as well.

    Try it around the corners, you can then run the magnet around the edges and drag the distorted area.
  8. Aug 5, 2003 #7
    Thamks Megashawn,
    I just totally screwed up my
    screen again with your "try it in the corner". Now it has these
    big curved moire' type bands of
    light and dark.

    The torment I am mentally devising
    for you will depend on how long it
    takes for these bands to go away.

  9. Aug 7, 2003 #8


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    first, let me say LOL

    next, I also suggested a way for you to correct it, did I not?

    It might not work on all screens, but I've seen what I described done before.

    Anyhow, I assume your joking since you started with a warning, so I'll continue laughing.
  10. Aug 8, 2003 #9

    No, your "dragging" didn't do
    anything but change the position
    of the bands.

    With a much smaller magnet I was
    able to erase the bands by going back and forth quickly across the
    screen horizontally while dropping
    a little bit lower for each pass.

    Your life has been spared.

  11. Aug 13, 2003 #10


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    Science Advisor

    Man, thats good. For a minute I thought you were gonna come all the way from the second largest zoo to the largest zoo just to exact your revenge.
  12. Aug 13, 2003 #11
    I was prepared to bring elephants.
  13. Aug 19, 2003 #12
    One time I did that by accident. I had my guitar amp sitting beside my tv and didn't really notice much of a warping effect but when I moved the amp so I could plug it in and have a go with the guitar, the left half of the screen was a wierd purple-ish green colour. It was awesome.
    Last edited: Aug 19, 2003
  14. Aug 19, 2003 #13
    You could rig something up that
    would move magnets around the screen as you play, or something
    that would change the current in
    electromagnets placed around the screen in synch with your guitar.

    I'm wondering if a person is recording on a VCR while doing
    this magnet thing if the VCR will
    record the distortions or just
    the original signal? If you could
    record the distortions you could
    start buliding some neat special effects for a music video.
  15. Aug 20, 2003 #14
    I'm not sure what the picture would do if I played while it was close, but I doubt it'd be recordable to a VCR because it's only affecting the screen, not the signal leading to the screen.

    You could, however, just videotape the screen with a videocamera. The quality would suck though.
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