When the set is turned on the picture has about a four inch space at the bottom of the screen. The picture is shrinking from the bottom, for the past few weeks. Now it's shrinking from the top also. I can bang the bottom of the set and the picture will fill the tube and then shrink again, sometimes it stays full. Hey, I'm a guy, if it don't work... Ya bang it, right? Thanks, Juls f8.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
Fault with the main power supply regulator board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. http://electronicshelponline.blogspot.com/
If you are watching widescreen format movie or tv programming on a non-widescreen tv, that is how it will appear. The widescreen is a wider picture so to show it on a less wide screen, it has to shrink down to fit. and leave blank space top and botton.
If the shrinkage is just the top & bottom then it is relatively easy/low cost fix. Most probably, a capacitor in the vertical section is nearing end of its life. This would be the biggest of the bunch and would be something like 47uF/50V.
If however, the shrinkage is on all four sides, then it is the master power supply that is at fault. Chances are the main B+ is getting low which cold be caused by the big filter capacitor or an erratic regulator. This is not a simple fix and would require the services of a qualified professional.
Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.
Open the TV amd turn it on in a position you can see the picture, possibly through a mirror. Now gently tap all of the metal heat sinks on the circuit board until you find the one that is sensitive it will have a small chip mounted vertically on it, with probably like 7-10 pins. The number on the chip will most likely be an "LA****" number. Now turn the circuit board (UNPLUG FIRST) over and resolder the pins. This is your problem 99% of the time. Be very careful there is High Voltage inside this TV.
All symptoms indicate a problem in the vertical circuit,the first thing to look for will be loose conection on the vertical output IC,sometimes this IC goes bad completly and it needs to be replaced.If you are familiar with soldering electronics you can take care of it but if you are not too familiar you can play it safe and take it to a servicer ,it will be a lot less expensive than if they come to your house.Let Us know how it goes or if you need more information.