If all you have is a straight horizontal line across the middle of the screen, you have a vertical deflection problem. This may be caused by the opening of the vertical coupling capacitor, an open winding in the yoke transformer, the vertical drive transistor might be malfunctioning, or the vertical output IC chip might be defective. You will have to check all of these, make sure that you have a schematic, a multimeter, and an oscilloscope. Here is why:
1) schematic diagram to know where parts are and the voltages and signals present at test points.
2) multimeter to measure DC voltages on the pins of components
3) oscilloscope to measure signals at test points shown on the schematic.
If you do not have a background in electronics please take your set to a repair shop, however if you have a background in electronics your troubleshooting will be around the vertical section if the tv.
Sep 16, 2007 |
JVC AV-27230 27" TV