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  #1  
Old 08-30-2010, 01:19 PM
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aidynphoenix aidynphoenix is offline
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Unhappy tv stopped working..

got a television from a neighbor. she told me it works "sometimes"
so i brought it home and pluged it in.. it worked just fine.
now after a few minutes white lines started appearing horizontially across the verry top of the screen.. after a day or so.. it just wont turn on anymore..

does this sound like it might be something that a noobie could fix if he knew what to look for? or what might be the culprit component?
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Old 08-30-2010, 01:43 PM
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So, place a photo of the set showing the entire front with the screen showing what you describe. Take the back off if you have the ability to do so and post a pick showing the full back/interior area. Write the model number with the posted pics. Somebody here may recognize the problem and give you a clue or tell you what to do. The other way to most certainly repair it is to search the correct category for info that most certainly is here that will let you know everything that is needed to do.
If you send me a round trip ticket and wine and dine me very well I can personally sit with you and even hold your hand if you like to help you click your mouse on all here that will solve your problem.
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Old 08-30-2010, 01:53 PM
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Brand, model number, does it have tubes or is it solid state?
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Old 08-30-2010, 03:26 PM
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Sounds like a vertical failure of some sort, pictures would be a great help. Probably a cap or possibly a transistor if the set is new enough to have them, which it sounds like it is by your description.
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Old 08-30-2010, 09:23 PM
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thanks for the attention to my problem..
ok i took some photos.. and gathered some information.
on the front it says Signature2000.. than on the back the model number is GRD15141
manufactured june 1990. service number is GRD15141f01

i powered it up in attempt to photo the white lines but it nolonger does that.. instead there is a really bright light thats streaches across the very center of the screen horizontally. as if the whole picture was squeezed together. audio is working fine tho.
im working on linking the pictures so you can see fullsize photos.
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Old 08-30-2010, 09:56 PM
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My vote would be for a bad cap in the vertical circuit. Don't run it for long as-is unless you can turn the brightness down (which you probably can't without accessing the menu.)

Search the circuit board for the vertical section and look, you might get lucky and see obvious signs of a faulty cap (leakage/corrosion around the base, a bulging top) otherwise you might have to just replace all the electrolytic caps in that circuit. Not a huge ordeal once the board is pulled. You can get those parts at RadioSchlock, though there are cheaper/better places. If it blew a transistor, though, you have a problem out of my league!
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Old 08-30-2010, 10:00 PM
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ok i noticed here. that in photo3.. one of the smaller caps have what looks like a brownish orange spot below it..
i will replace it tomorrow when it is less risky of getting shocked because i just had it plugged in..

i will remove the board as much as possible.. to reveal the underside. and check for broken solder connections while replacing that cap.. also.. should i try and locate a schmatic and see if there are any fuzeistors or picofuzes. and test them?
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Old 08-30-2010, 10:01 PM
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thanks verymuch for the reply bgadow..
now is it possible for me to completely remove the board.. by that specifically i mean the really fat red wire?
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Old 08-30-2010, 10:19 PM
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You need to discharge the high voltage first. Here is my favorite method of doing it: Get a large screwdriver and a wire with alligator clips. Connect one end securely to the metal shaft of the driver and the other end securely to something grounded on the set-there will be some sort of spring that makes contact with the outside of the picture tube and it will have a small wire connected to it, probably running somewhere on the chassis. Hook the other alligator clip to that spring or that wire. There might be a metal frame for that chassis which will work, too. Now, with one arm behind your back, and your hand off the screwdriver shaft, poke the tip of the screwdriver under the "suction cup" HV connector on the picture tube. When you make contact with the connection you should hear a "snap" from the HV discharging. Do it a couple times. Then you can grasp the rubber cup and pull the connector off the tube. Usually you have to squeeze it and wiggle it around some. Before you put it back on there, I would discharge the HV again. They can build up a charge just sitting there.

The HV wouldn't kill you; but you sure wouldn't like the experience!
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Old 08-30-2010, 11:26 PM
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Looks like a Thomson made set - CTC157-166 possibly. If so, all of the 500-series caps should be checked/replaced. C4505, a 220uf/35v is a common culprit, as is C4502. Both would be marked C505 / C502, as they leave the prefix off most board markings. The one with the leakage in the photo would be a safe start!

Cheers
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  #12  
Old 08-30-2010, 11:32 PM
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hehe awesome.. thats simple enough..
i wasent sure if it was ok to remove the suction thinggy.. thought there might of have been gas or something inside there.
now putting it back in should be simple too right? just squeeze it and set it in?
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Old 08-30-2010, 11:35 PM
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Quote:
Originally Posted by Findm-Keepm View Post
Looks like a Thomson made set - CTC157-166 possibly. If so, all of the 500-series caps should be checked/replaced. C4505, a 220uf/35v is a common culprit, as is C4502. Both would be marked C505 / C502, as they leave the prefix off most board markings. The one with the leakage in the photo would be a safe start!

Cheers
Awesome! i will replace all i can as soon as i can, hopefully tomorrow.
is it wise to try it after replacing them?
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Old 08-31-2010, 08:23 AM
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I'm pretty sure the vertical IC is toast. The IC dies when the caps dry out. The caps cause the lines on the top of the picture. When the IC dies it causes just the white line across the screen.
Changing the caps near the IC and the IC usually bring that set back to life! That set can provide a great picture once fixed and set up properly.
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  #15  
Old 08-31-2010, 10:40 AM
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ok so if i replace the caps, and it doesnt fix it.. i should then replace the IC..
does the IC look like a transistor? (small black thing with 3 leads on it?)
it would probably be nearby right?

im going to look for a schmatic now..
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