In rereading my note, I neglected to mention that I plugged it back in. Obviously. The TV made its "on" sound from its own speakers.
I have a new 52" Samsung 850. While watching a blu-ray disk the screen went black. Since the cables all seemed fine, I unplugged the TV from power and waited a minute. Then I pressed the "Content" button to switch the TV to its internal content. If you look at the screen just right, you can just barely see the large print "Art" "Relaxation" etc. menu. Using the remote to query "source" also shows an almost imperceptible menu (think 99.99 black against 100.00 black), but the screen is totally black.
I assume it's not possible to accidentally select a value of "0" for backlighting.
I'm guessing this is a backlight failure. Any suggestions?

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