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George Jetson George Jetson is offline
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Default Samsung 27" TV doesn't work.

Someone gave me a Samsung 27" TV, Model TXL2791F. When I tried to turn
it on it did nothing. No indication of power at all. I opened it up and
checked the fuses. All good.

I got a copy of the schematics, and did a little circuit tracing.
There's a component called a flyback transformer, which is connected to
a component called a high voltage tripler, which is connected to the CRT
high voltage anode. There's a picture of it at
http://www.wehaveparts.com/index.cgi...=1553&cart_id=
1146478751 . The picture says it's a flyback transformer, but according
to the schematic it's the tripler. The schematic just shows a box. No
internal wiring.

The thick wire shown in the picture goes to the CRT anode, the thin wire
goes to a ground, and the hole is for a thick wire from the flyback.

When I pull the ground off, I can turn the TV on with the switch as well
as the remote. After removing the ground, when I plug it in I hear the
slight crackling/humming sound that means the set is powering up, and a
red LED comes on that means the set is powered up but off. When I press
the ON switch or the remote, the LED turns green, and I get a tone that
means I need to set up the time, channels, etc. I get no picture, of
course, because there's no voltage to the CRT, but everything else seems
to indicate that the TV is starting to power up normally. When the
ground wire is connected, presing the switch or the remote gets no
reaction at all.

No, my question. Would this indicate a problem with the tripler? Or the
flyback? What's a good way to test? I am familiar with radio and
computer repair, but I've never worked with televisions, and I don't
have any high voltage test equipment. Thanks for the help.

Oh, and I'm aware that the voltages in a TV can kill me, so I take
proper safety precautions, so no need to remind me. Thanks for the
thought, though.