My older brother came home to turn on the TV, and according to him, there were vertical lines on the screen for a few seconds, then the picture went completely blank. Sound worked and so did the remote and buttons on the front. He turned it off, I unplugged it and let it sit for about 20 minutes.
I powered it on again and was greeted with the same stuff, except this time the OSD that shows up when you change inputs would appear (still no actual picture) for a short time, then jump around the screen, distort (parts of it would disappear and sometimes reappear elsewhere). After a couple rounds of that, the screen went completely black again. Looking closer, I could see very faint, moving, horizontal lines. They looked to be about a hundred pixels wide (?) and moved fairly smoothly. This was with an input signal (cable box).
Thing is long out of warranty. Figured the problem was most likely either something to do with the control circuitry for the panel or its power supply.
I opened it up, and when the TV was turned on, I heard a high frequency buzzing sound from the PCB at top right.
Came here and found the trick where you disconnect the LVDS ribbon from the board with the inputs to the board with the microcontroller, and short the two points to get color bars. No color bars appeared.
Then, I measured the voltage rails coming from the huge SMPS board in the center to what looks like another fairly hefty power supply board on the righthand side. "M5V" was +5.15V, "VA" was 55.1V and "VS" was 202V. All seemed to be steady and constant.
Am I on to anything here? What would you guys suggest? Thanks in advance :p
Also, let me know if anyone wants more photos.
I powered it on again and was greeted with the same stuff, except this time the OSD that shows up when you change inputs would appear (still no actual picture) for a short time, then jump around the screen, distort (parts of it would disappear and sometimes reappear elsewhere). After a couple rounds of that, the screen went completely black again. Looking closer, I could see very faint, moving, horizontal lines. They looked to be about a hundred pixels wide (?) and moved fairly smoothly. This was with an input signal (cable box).
Thing is long out of warranty. Figured the problem was most likely either something to do with the control circuitry for the panel or its power supply.
I opened it up, and when the TV was turned on, I heard a high frequency buzzing sound from the PCB at top right.
Came here and found the trick where you disconnect the LVDS ribbon from the board with the inputs to the board with the microcontroller, and short the two points to get color bars. No color bars appeared.
Then, I measured the voltage rails coming from the huge SMPS board in the center to what looks like another fairly hefty power supply board on the righthand side. "M5V" was +5.15V, "VA" was 55.1V and "VS" was 202V. All seemed to be steady and constant.
Am I on to anything here? What would you guys suggest? Thanks in advance :p
Also, let me know if anyone wants more photos.
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