Looks good (unfortunately). Could be the main IC on the T-con itself is bad, since you do get some picture, so the main board is sending something, but it's not "rendered" properly. Other more experienced users are of course welcome to disagree, that's why we're discussing.
I am wondering if it could be some of the caps I have used. as I did mix it up a bit with brands.
I have a ESR meter if you know what caps for the picture on the PSU I should be measuring let me know .
Unless you used caps that you recovered from another board (used ones), you shouldn't worry about what brand they are, as it shouldn't matter. The brand only makes a difference in how long they last over time AFAIK.
Also, the power supply board is not directly involved with the picture: it supplies the voltages to the main board and T-con board which then do some stepping down of their own, so as long as the TV is turning on and displaying something, the PSU is likely not the culprit. Noise on the output of the PSU has to get pretty bad to affect anything, by which point the TV is likely not going to turn on at all, but your is, so there's a problem with an IC somewhere. A scope would be handy to analyse the power going into the T-con and main board and ensuring it's ripple-free.
if it is a IC I have a microscope to use for the fine soldering.
Could be the main one (in the middle of the board) which is not replaceable from where I stand, because you can't find it easily, plus the price and labour would outweigh the cost of a replacement T-con. Good on you for having a microscope though...that's another thing I lack.
Would that reading be in relation to GND ? If so, repeat the measurement in ohms just for the sake of thoroughness. Still, pins 4 and 5 give you the boosted 15v output, which you seem to be getting, given you last results: AVDD = 15v. If there were any dead shorts, you probably wouldn't get any picture at all.
This is a good time to measure VGH (voltage gate high) and VGL (voltage gate low) as well since the pins are clearly labeled in the datasheet for the TPS. They are pins 10 and 11. From what I've seen, "ghosting" occurs if VGL is not functional (the screen is not "discharged" and the picture gets stuck). Conversely: if VGH is not "charging" the screen, well, quite predictably, you get no picture. These seldom fail though and from what I've encountered so far, if VGH/VGL are not up, the fault is not in the T-con, but in one of the buffer boards where there's a short that kills VGL/VGH and it's not repairable at that point (the short is most likely in the COF - chip on flex)
Pin 11 should read negative (usually -5/-6v). Try and see if there's a pad labeled VGL connected to that pin (there's a diode in series with that pin, so don't measure AT the pin, measure after said diode). The example schematic in the TPS's datasheet illustrates this. See how there's a diode D2 on the VGL pin there ? Measure after it and see what you get. Should be negative. If not you could be getting closer to the issue now.
Would that value happen to appear at the test point marked V_OFF ? If so, it would seem they're not calling them VGH and VGL but rather V_ON (slightly higher, towards the mounting hole) and V_OFF, which is the same thing.
The value would seem right...a bit low, but should be within spec (the datasheet for the panel itself tells you exactly what it should be).
EDIT: also, could your describe, or better yet, post a picture of what the picture is doing currently ? I missed the video.
Wow that's bad...you could try heating up the main board like someone else suggested just to see what happens. Must admit I haven't seen anything quite like it, but that rainbow of colors could point to a faulty MB too...
Would that value happen to appear at the test point marked V_OFF ? If so, it would seem they're not calling them VGH and VGL but rather V_ON (slightly higher, towards the mounting hole) and V_OFF, which is the same thing.
Not necessarily. Actually this is the first T-con I've seen which calls them that. Samsung doesn't manufacture the boards anyway, so the original producer is free to mark them whatever they want if I'm not mistaken.
Could also be a bad LVDS cable, though I doubt anyone messed with it. Still worth trying to disconnect it, plug it back in at either end, jiggling it around, you know just to rule it out.
Could also be a bad LVDS cable, though I doubt anyone messed with it. Still worth trying to disconnect it, plug it back in at either end, jiggling it around, you know just to rule it out.
Have had this disconnected a few times after I got the tv back cables look good no ones been messing with them.
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