Re: Why will my strong magnet (4000 gauss) damage my TV screen?

     I don't know much about CRT's but there are magnetic components in 
there that retain some permanent magnetic moment if exposed to a large 
field.  This creates small stray fields which exert a force on the 
electrons and diverting them from their proper paths.  This distorts the 
image.  The time the field is appled has no bearing on the "damage" 
done.  The problem is easily corrected by "degaussing" the CRT.  This is 
done with a special device or a large (18 inch diameter) coil with 
several hundred turns plugged into the wall.  Don't leave it plugged in 
too long!!  It will get hot!