"Arthur Jernberg" writes:

Probably the crt getting weak

More likely it is a case of "doming". The intense white represents
high current electron beams which are causing the shadow mask in the
vicinity to heat, expand slightly, and distort, which is
manifesting itself as a color purity shift to green.

Just turning down the brightness a bit will probably eliminate it.

--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
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