Toshiba Model 53HX71: Bottom half of screen and sound is fine; top half of screen has collapsed to a horizontal line in the middle of the screen. Repairman I spoke to briefly said it probably won't be...
Your TV has vertcal scanning problem. All picture tube based TVs have, both vertical and horizontal scan to spread the picture to entire screen. When vertical scan section meets with a fault, the picture will collapse horizontally and fi horizontal scan section has a troubl, picture will collapse vertically. Your TV s fault , we technically say, to be vertical foldover. This is due to the vertical output section, a circuit part, inside the circuit board of your TV.
To rectify this fault you must open your TV. Unplugh it from the power socket, and open it. Locate the vertical output section, which is easy to do. Look at the deflection yoke, the coil fitted on the neck of the picture tube, and you will see four wires from it going to the main circuit board. Out of which, two will be thick, normally red and blue in colour, connected to the opposite direction on the deflection yoke, and the other two will be thin. follow the two thin wires, said later, and you will reach to a plug in point on the printed circuit board.
Before doing anything, just look at the soldering of that section carefully for any loose soldering, or bad soldering. Usually, the components in the vertical output section will get heated during working, and ahve a cahnce to get loose contacted soldering joints. Just resolder all the suspected points by applying a little more solder, and see the effect. If thi doesn't help, check the IC used in that section for trouble. Some capacitors will be there in this section, will get dried as aging, replace them first, as they are ver few in numbers, When replacing capacitors, note their polarity, as electrolytic capacitors have both positive and negative terminals like torch cells. Before replacing the vertical IC, replace all the capacitors, especially, two or three large capacitors on that section. Just do these and if you want any more assistance feel free to contact me through Fixya. OK
Dec 08, 2010 |
Toshiba 27AF42 27" TV