You see that effect on sets that were moved recently. It's not user serviceable and the cost tends to be as much as a new set. If you want to read more, use google and read in avsforums. Sorry to read about your loss.
Bob
I have a SONY BRAVIA model KDL52XBR9. Recently,
a translucent dark band, covering about one-quarter of the screen on the bottom, has appeared when I turn the
set on - sometimes it quivers. It goes away after about
five-ten minutes but I am worried that something is about go really bad.
Has any experienced this? If so, what needed to be done to stop this problem.
Tae

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