Samsung 27" TV doesn't work.

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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?product=&pid 53&cart_id1146478751 . 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.
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George Jetson wrote:

in the model your speaking of there is only a FLYBACK transformer, the tripler is built in the problem your having is the flyback replace it and you should be good to go VERY VERY comon problem on sam dung
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It appears to be two distinct components. This is the flyback:
http://i25.photobucket.com/albums/c95/greree/flyback.jpg
This is the tripler:
http://i25.photobucket.com/albums/c95/greree/tripler.jpg
How do I test it to see which it is? Thanks.
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For starters, you can try simply resoldering the connections to the flyback. These pins come out of the bottom of the flyback, and extend trough the opposite side of the circuit board. This is a heavy component and the development of ring cracks are very common. The cracks can even be difficult to see with a magnifying lens.
CWM
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wrote:

Unless this is just a hobby for you TVs are usually like Bic lighters. When they go bad you toss them. If you just start "easter egging" parts in there you could have more than the TV is worth and still not fix it. Sometimes is is just one thing but if this thing was hit by a power surge you could have smoked several thiings
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snipped-for-privacy@aol.com wrote in

This one cost $700 new, and is better than the one I have now. If I can fix it for $50 or $60 it'll be worth it. If I can't I'll toss it.
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George Jetson wrote:

If you know what you're doing it shouldn't be hard to fix, otherwise take it to a shop or at least find a friend who's experienced in working on TVs or you'll more likely make it unrepairable.
Do you have a multimeter, soldering tools, and a basic understanding of how a television set works?
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Yes to all, plus I have a set of schematics for the TV.
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You may want to check for open 1 ohm or so resistors on the secondary side of the fbt, sweep derived supply, whatever you want to call it.
George Jetson wrote:

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James Sweet wrote:

Do you, or do you just jizz on the circuit board?
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You paid *way* too much or are quoting the price of 15 years ago. $450 will buy you a well made 32" set; your tv can be replaced for under $300.
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Neither. This TV came out in 2001 with a MSRP of $699. I got it for free.

Why would I want to pay $300 to $450 for a new TV, if I can fix this one for $50 or $60?
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I haven't tried to buy a flyback for a long time. I suspect you will have problem finding the right one and at a reasonable price.
Charlie
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It doesn't appear to be the flyback. It's actually the tripler, and I found one for $38 online. If it does end up being the flyback, I'm sure I can get one from the same place.
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George Jetson wrote:

Because it's a gamble. You can spend 50 to 60 bucks in an "attempt" to fix it. If your time and effort is worth anything at all considerably more than that. And when the new fly-back is in place there is a very good chance that the set will be just as dead as it is now.
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That's why I'm asking for advice on troubleshooting. Besides, if I wasn't trying to fix the TV, I'd probably be WATCHING TV, or playing on the internet, so so my time and effort isn't worth all that much.
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George Jetson wrote:

Just be mindful that when working on a set (even one completely disconnected from power) that there is more than one place you can touch that will light you up pretty good. The old rule being "one hand in a pocket". A 27 inch will have about 30,000 volts stored in the tube and some of the larger capacitors can get your attention as well.
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Rick Brandt wrote:

Hi...
I think it specified the "left" hand in the pocket... :)
Take care, be safe, and happy holidays.
Ken
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Ken Weitzel wrote:

So left-handed people can't work on TVs?
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CJT wrote:

Hi...
Hehehe.. none that I ever met :)
Seriously, the theory was that the left hand (shoulder) was nearest the heart, so the path of current flow would be least likely fatal from the right hand to wherever it was going, rather than the left.
Take care.
Ken
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