Greetings,
I have a quick question for some of the more experienced techs out there.
(my background: I do component level work and am somewhat experienced with TV repairs)
"40 RCA RLDED4030A-B-RK LED LCD TV, about 2 years old, the set experiences distortion in the upper 1/3 of the screen, distortion is not static (at least not all of it),
It appears as what seems to be fast rolling reflections of what is displayed on the lower screen sections and also some light colored horizontal lines.
A thing to note, if a large portion or all of the screen is black, then the distortion would almost be unnoticeable.
It appears right from power on, on the white background with the RCA logo.
Another note is that some times the screen will go black, disconnecting and reconnecting the LVDS cable brings the picture back.
This set uses one main board which incorporates all functions and has the LVDS cable going to the small board that is attached right to the LCD panel, it is attached with permanently bonded flex cables and cannot be removed from the panel in an easy way.
The board is only attached with 2 cables, and there are no more boards or flex circuits attached to the panel anywhere at all.
The panel appears to be made by Samsung, and the long and narrow LCD board contains the following ICs:
Samsung LTF62B0 (larger IC adjacent to the LVDS connector)
RT6929 & RT6930 (to the left of the LVDS connector)
My attempt to find info or datasheets on those ICs didnt yield anything useful.
Things attempted:
-Disconnecting some of the LVDS wires, which causes the image to either disappear or freeze (including the distortion) and fade away
-LOTS of wiggling while the set is operational, mainly of the long narrow board and ribbon cables
-Applying moderate heat with a heatgun to the board and the ICs
-Thorough inspection with magnifying glasses and good light for anything unusual on the LCD board
-Applying moderate heat to all outer sides of the LCD panel
Aside from the image disappearing completely in a few cases where I've heated up the ICs too much (and then coming back when they cool for a minute), no change at all has been noted in the distortion.
I would like to get some advice, whether the issue is possibly with one of the ICs on the long board attached to the panel, in which case I assume that I could replace it (the IC), or whether this can actually be a panel defect, since judging by the only two cables connecting it, I assume that a lot is going on inside the glasswork as well.
Please correct me if I'm wrong here, but I'm pretty sure that this type of interference wouldn't be caused by an issue on the main board or the controller on it.
Thanks in advance for any input, and please see the attached images.
I have a quick question for some of the more experienced techs out there.
(my background: I do component level work and am somewhat experienced with TV repairs)
"40 RCA RLDED4030A-B-RK LED LCD TV, about 2 years old, the set experiences distortion in the upper 1/3 of the screen, distortion is not static (at least not all of it),
It appears as what seems to be fast rolling reflections of what is displayed on the lower screen sections and also some light colored horizontal lines.
A thing to note, if a large portion or all of the screen is black, then the distortion would almost be unnoticeable.
It appears right from power on, on the white background with the RCA logo.
Another note is that some times the screen will go black, disconnecting and reconnecting the LVDS cable brings the picture back.
This set uses one main board which incorporates all functions and has the LVDS cable going to the small board that is attached right to the LCD panel, it is attached with permanently bonded flex cables and cannot be removed from the panel in an easy way.
The board is only attached with 2 cables, and there are no more boards or flex circuits attached to the panel anywhere at all.
The panel appears to be made by Samsung, and the long and narrow LCD board contains the following ICs:
Samsung LTF62B0 (larger IC adjacent to the LVDS connector)
RT6929 & RT6930 (to the left of the LVDS connector)
My attempt to find info or datasheets on those ICs didnt yield anything useful.
Things attempted:
-Disconnecting some of the LVDS wires, which causes the image to either disappear or freeze (including the distortion) and fade away
-LOTS of wiggling while the set is operational, mainly of the long narrow board and ribbon cables
-Applying moderate heat with a heatgun to the board and the ICs
-Thorough inspection with magnifying glasses and good light for anything unusual on the LCD board
-Applying moderate heat to all outer sides of the LCD panel
Aside from the image disappearing completely in a few cases where I've heated up the ICs too much (and then coming back when they cool for a minute), no change at all has been noted in the distortion.
I would like to get some advice, whether the issue is possibly with one of the ICs on the long board attached to the panel, in which case I assume that I could replace it (the IC), or whether this can actually be a panel defect, since judging by the only two cables connecting it, I assume that a lot is going on inside the glasswork as well.
Please correct me if I'm wrong here, but I'm pretty sure that this type of interference wouldn't be caused by an issue on the main board or the controller on it.
Thanks in advance for any input, and please see the attached images.
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