Re: Degauss TV screen


"JRRR" <jrrroach@xxxxxxxxx> wrote in message
news:1167434719.534143.218410@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
A magnet was swiped across my TV screen, leaving a purplish swath. Is
there a way to fix this problem?


All crt tv's have a built in degaussing circuit. They use a PTC (positive
temperature coefficient) resistor to limit the current through the
degaussing coil. Therefore when the TV is first turned on, the coil sees a
large current, as the PTC heats up the current decreases (resistance
increases) until it reaches a very low current that won't affect the CRT
deflection. When the set is turned off, the PTC cools down, lowering it's
internal resistance for the next TV turn on. If you just cycle the set
normally eventually it should correct itself.


.

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