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Something weird

  1. Apr 30, 2004 #1
    have you ever taken a portable phone (i have a hunch that a mobile would work too) and (when it's not on or anything) ran the ear-end (the end with the antenna) across your computer screen? it makes a weird sort of electric shadowy thing...what's happening? :confused:

    [i should mention that this is a normal, old-fashioned screen - not a flatscreen lcd]
    Last edited: Apr 30, 2004
  2. jcsd
  3. Apr 30, 2004 #2


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    I'm not sure what you mean exactly, but it sounds to me like magnets in the phone are deflecting the paths of the electrons (remember a basic monitor (not a LCD one) is basically a cathode ray gun behind a luminescent screen
  4. Apr 30, 2004 #3
    magnets - right, i tested this by waving my electric guitar's pickups in front of the screen - you're absolutely right...i wonder if this is bad for my monitor... :rolleyes:
  5. May 1, 2004 #4


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    I think it most certainly is. I tried similar experimentation with a color TV, and I messed the picture up but good! When I got my computer monitor, I noticed that it had a "degauss" feature. If your monitor has this in the main menu, you might be able to fix any harm you could do, but I've never had the nerve to test that hypothesis.
  6. May 1, 2004 #5
    Honestly, I just like to play witht the DeGauss button every once in a while because it looks nifty. Is that bad? (For the monitor, that is)
  7. May 1, 2004 #6
    Keep loudspeaker magnets away from monitors, and TV's especially. I believe the resulting concentrated flux of electrons can burn out phosphors.
  8. May 2, 2004 #7
    The degauss feauture will not harm your monitor, and in fact helps correct occasional problems of this nature. Just did it myself right now, and my text looks a little clearer I must say. I suppose one would not want to do it 12 times a day, though. Once or twice a month should be just fine.
  9. May 2, 2004 #8
    I also have heard that some monitors automatically degauss themselves whenever thay are turned on.
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