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Smarty

On 6/1/2013 11:01 PM, wrote:
On Jun 1, 8:19 pm, "Phil Allison" wrote:
"Smarty"

Sounds like a purity problem. Start by degaussing it.
A purity problem would NOT have black and white looking ok as reported in
the original post nor would it result in explicit color replacements as
reported.
** The set is a 19 inch Sony - so it is a Trinitron type.

I suspect the behaviour is typical of Triniton with a magnetised aperture
grille. The degaussing thermistor may have failed in the set and at the
instant of failure left with a parting blow by magnetising the grille.

The OP can check for this by noting if the usual switch on " bong" noise
still happens.

He can also bring a magnet near ( not touching) the screen and see if that
tends to fix various areas.

Sounds like a color demodulation problem.
** Not likely.

... Phil
What Phil says. I did color tv repair for 20+ years, and it is
amazing what magnetization can do. If there was a lightning storm
while you were gone, that would explain a lot.
This is altogether surprising to me, but then again I virtually never
did TV repair. I have a bit of trouble understanding why a magnetized
shadow mask or aperture grill would still allow a black and white image
to be correctly displayed. If beam alignment were 'spoiled' by residual
magnetic contamination of the CRT near the faceplate or if the purity
rings were not doing their job, then the outcome should be color
blotches regardless of whether chroma saturation is absent or present. I
hope this specific problem is eventually solved so I can hear the actual
cause of the problem. This old dog loves to learn new tricks !