Basically I am wondering what could be causing the problem. Lately it is working perfectly fine after I took the back off the tv and investigated the bottom of the board only to find some soldering that was overdone with big blobs on some points and messy flux jobs on specific parts of the board. I tried to get some of it off on parts of the board but it was just really hard and I don't have any alcohol on hand to clean it. After finding what it seemed to be no possible cold solder joints I put the board back in and connected the sound and the picture tube back up. Then I turned the tv on and seen the picture was flat. I gave it a small tap and the picture went to where it was suppose to be. Afterwords I adjusted the screen and focus knobs in the back the best I could and then it seemed to stop going flat. So is that all the problem was a little bit of a adjustment for the screen and the focus if so then that is a little interesting.
If its going to a line left to right---broken or bad solder connections at the vertical output chip---
SOURCE: tv keeps flat lining and shrinking picture
If this is a crt tube tv. Your vertical ic is loosing its connection with the board. Better to quickly resolder it or reflux it with a new lead. Before the IC fail for good.
SOURCE: Flat line on Toshiba tube tv
It could be the vertical output IC, but there may be other possible causes which include:
- bad solder contacts on deflection yoke connectors or dirty connector contacts (on the circuit board and / or on the picture tube neck)
- bad solder contacts on the vertical output IC or associated components (check for little cracks in the solder around the pins, these are so called "cold" or bad / broken contacts)
- power loss to the vertical output IC - check for any burned resistors or other components around that IC, assuming you know which one it is - see which ICs are connected to the wires going to the deflection yokes (coils) on the picture tube neck and check them well.
You need to resolder any bad contacts, clean any dirty pins on the connectors and replace any burnt out components (assuming you can still determine the type or value of the component).
Since you mentioned the problem occurs once in a while, this means that the IC probably fails when it warms up, which can often happen if there are loose connections or bad solder contacts.
Anyway, it could turn out to be a faulty IC, i just suggested a few other things that can be fixed quite easily, and possibly without the need to replace any of the components.
regards
3rq8 (Triarcuate)
SOURCE: Toshiba 36 inch TV that has a shrinking picture.
Rod,
To ask those questions indicates a lack of knowledge in a very specialized area. This is not really a DIY. Soldering is a skill, especially in an object that has fine tracks. Spill excess solder on the tracks and you will short out the whole unit. Overheat a component with a soldering iron and it will kill it. There is also the Radiation risk at the rear of the TV as well as High tension. You need to know how to ground the unit when opening it to prevent electric shock of a lethal type.
I suggest you call a professional in to do this or take it to a local repair shop. This also involves unsoldering an IC Chip and replacing it. There are numerous money saving DIY's on here all thinking they can do it cheaper and just as well as a trained repair tech. Some actually get in and do the job, but 96% are back in a week or so with either the same problem or greater problems than before.
You have to know WHY those things occurred, they may have been set off by some other part failing somewhere up the line. and technicians know where to look and have the equipment to test the integrity of the whole system as well as generating a test pattern to align the convergence and color wheels. Take my advice for what your life and health may be worth, take it to a repair man and have it done properly
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These a good solutions. Thank you for responding. If I get a chance I will see if I can fix the issue. For now I think it should be fine. I am not entirely worried about it as it is working fine and I have 2 other working tvs.
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