To prevent the Earth (or anything else) from permanently magnetizing the CRT, all color monitors use a degaussing coil. A degaussing coil is a demagnetizing coil that surrounds the outside of the picture tube. The degaussing coil is powered by volts AC. The rapidly changing field quickly demagnetizes the CRT by scrambling any molecules that might be aligned through magnetic attraction.

         But the degaussing coil can't remain continuously energized while the monitor is in normal operation. Disregarding the fact that it will burn-up if left continuously energized, the magnetic field produced by the coil will produce some radical distortion in the picture. Most monitors use an ?automatic degaussing circuit to control the coil. The degaussing coil is only activated when the monitor is first turned on, and then only briefly at that.To reactivate the coil, the monitor must be allowed to cool for ten to twenty minutes.

         VRK spectrum produce De Guassing Coil of television and pc monitor for the international famous brand.