Picture quality the picture quality seems to be going. The picture will suddenly go concave on both the top and bottom of screen and at the same time a lot of colorful horizontal squiggly lines go through whole screen. Will sometime stay like this for a long time and other times just a few seconds. Does not seem to matter if TV is warm or cold. And it is getting more frequent. Is there any soultion to this problem?

Its a rather old set to be fixing, if off at top or bottom=vertical deflection problem, if sides are concave pin amp circuit---the fact you can turn it on/off several times etc suggests to me maybe bad solder connections somewhere in those circuits.

AS old as this set is keep in mind a lot of the parts for it are no longer available so be careful about spending a ton of money to fix it.

HI!
can you take a picture to your tv to see exactly what happen to your vertical problem!? then you can post here thanks!

Sounds like the convergence output ICs failed, when they fail they can also open fuses and or resistors.

HI, this is a failed convergence chip that is located on the convergence board. it will need to be replace ASAP. you can just replace the chip or , you can order a new board.

Replacing the chip can be a rough job if you don't have tech experience. if you are a fluid tech and you can solder and know your way around a circuit board, just replacing the chip will cost less. if you are not an experienced TV tech, i recommend a service call to the nearest TV tech to replace the convergence board.

dumped it.

I wouldnt reccommend that you try to fix it as it is a lot easier to make it worse that better. Basically your color guns have gotten un focused and will need to be adjusted. Call a tv tech and they can usually fix it for a decent price.

Bad convergence IC's ....change both for reliability...part number
STK392-570...located on center PC board.................T.

sounds like you need the convergence kit part number X480295

sony trinitron colour 29ins tv its black and white not colour but the teletext is colour

Problem 1. Color patches at lower corners. These are caused by magnetic sources close to the TV. Do you have any Speakers close to the sides of the TV? Are they Magnetically sheilded? No? Move them away from the TV. Problem should then resolve itself in a couple of days. Problem2. Screen Slumping. Most likely a problem with the Pin cushion correction ckts. Get a good technician to have look. cost should not be much. Under 100$ plus Technician fees.