Wayne Parham Messages: 18755 Registered: January 2001
Illuminati (33rd Degree)
The magnets won't actually damage the TV or its picture tube, they'll just interfere with the electron beam path. The electron beam is deflected by the yoke, which is a pair of coils placed around the neck of the picture tube. The yoke's job is to deflect the electron beam to position the scanlines. When an external magnetic field is present, it interferes with the operation of the yoke, essentially offsetting the deflection of the electron beam. There is a residual effect that remains after you remove the magnet, but it can be corrected by degaussing the tube. It's very much like using a tape head demagnetizer.