Permanent Magnets & TV screen

In summary, if you hold a strong permanent magnet up to a TV screen while it is on, the image will become warped. This effect takes months to clear up.
  • #1
6,510
1,290
DO NOT TRY THIS EXCEPT ON A JUNK
TV OR MONITOR

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.

-Zoob
 
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  • #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.
 
  • #3
Johnathan,

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
cool.

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.

-zoob
 
  • #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.
 
  • #5
Degauss

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.
 
  • #6
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.
 
  • #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.

-zoob
 
  • #8
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.
 
  • #9
Megashawn,

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.-zoob
 
  • #10
Man, that's good. For a minute I thought you were going to come all the way from the second largest zoo to the largest zoo just to exact your revenge.
 
  • #11
I was prepared to bring elephants.
 
  • #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 weird purple-ish green colour. It was awesome.
 
Last edited:
  • #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.
 
  • #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.
 

What are permanent magnets?

Permanent magnets are objects that produce a magnetic field without the need for any outside source of energy. They are made from materials such as iron, cobalt, and nickel, and have a north and south pole that attract or repel other magnets and magnetic materials.

How are permanent magnets used in TV screens?

Permanent magnets are used in CRT (cathode ray tube) TV screens to help direct the electron beam that creates the images on the screen. The magnets are placed around the tube and can be adjusted to control the direction and focus of the beam, resulting in a clearer and more precise image.

Can permanent magnets damage TV screens?

No, permanent magnets do not have any harmful effects on TV screens. In fact, they are specifically designed and placed in CRT TVs to improve image quality. However, strong magnets placed near newer LCD or LED TVs may cause distortion or discoloration, so it is best to keep magnets away from these types of screens.

How do permanent magnets in TV screens work?

The magnets in a CRT TV screen work by influencing the movement of electrons in the electron beam. The north and south poles of the magnets create a magnetic field that alters the direction of the electrons, causing them to strike specific areas on the screen to create the desired image.

Can permanent magnets in TV screens lose their magnetism?

Yes, over time, permanent magnets can lose some of their magnetism due to factors such as exposure to heat, shock, or strong magnetic fields. However, in most cases, the magnets used in TV screens are designed to retain their magnetism for a long time, and the loss is usually minimal and does not affect the performance of the TV screen.

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