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What's wrong with my Tele?

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Cursewords

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I bought this TV used from a networking group on Facebook about 3 weeks ago.

The model number is: LE26R77DB
Now it's started exhibiting these issues with the screen:

This is the picture when I press any menu/guide/overlay button
2nOywdM.jpg


This is the only issue that displays when watching a TV channel. (It's a top horizontal bar of pixels that flash)
qeaHcp8.jpg


Another picture of the pixels that display when an overlay is open on the screen
zF9qk70.jpg


When the TEXTTV is open, this rainbow horizontal bar of pixels displays at the bottom:
GWQusoq.jpg


When my laptop plugged into the TV via HDMI there's 3 horizontal lines of flashing pixels at various parts of the screen:
W2JVzsA.jpg


On various parts of the corners of the screen are these weird black pixels, but they are only noticeable on the HDMI connected screen:
CKFaGTA.jpg


I've tried:

1. Giving the screen and bezel area a tap.
2. Giving it a bit of a smack
3. Twisting the bezel/screen
4. Plugging in another machine (PC) to see if the issue exists there also.
5. Changing the picture display settings/zoom/etc.
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1. In addition to all of these issues there are some others:

1a. When a device is plugged in and tuned on (like an Xbox) but a TV station shows on the screen, there can be seen some bleeding through the picture. It's faint but present. It doesn't always look like the current screen displayed on the Xbox, but a previous screen. It only displays when the Xbox is on.

1b. No matter what resolution I tell the TV to display when plugged into my laptop via HDMI. It doesn't ever show the WHOLE picture. It always seems zoomed in. No matter what resolution I choose for it to display. Also it will only display at '30Hz (Interlaced)' and the only other options are 25Hz or 20Hz (both interlaced). I would expect an option of at least 60Hz or something, and a progressive scan...

I haven't tried opening it yet. It does seem to be a bit of an old TV, and it was very cheap to buy. However it was working fine before I bought it. It's definitely out of warranty.

I consider myself pretty good at fixing stuff (once I know what the problem is).

Is it a panel problem, or could it be an issue with the rendering chip or something far more technical? Tapping/smacking the TV hasn't made one iota of a difference.

Also when my laptop is plugged into the TV via HDMI, no matter what resolution I select it will never display the whole picture. The picture always looks zoomed in.
 
Given your description and photos, I would say most likely T-Con board failure. This could also be brought about by a power supply rail going to the T-Con being squiffed. Buy a power supply kit for the power supply and replace the T-Con board carefully. Watch and take precautions for static electrickery around the T-Con board, they are super sensitive to it and can easily be killed by poor handling :)
 
Inspect for any slightly bulged Cap lids. everywhere

memory effect in LCD's is common which can be an analog bias level in the LCD or just aging.
 
Nigel will have more knowledge than me on this, but I was under the impression that overlays are run at a different frequency than the input!... I used to have an old Amiga hires monitor that used to do this... It only affected the overlay.. The picture was fine.... It was easier for me as the overlay circuit was separate and could be replaced quite easily... Its probably a miro that does it nowadays.... As tony said a caps gone south...
 
As others have suggested, Samsung's are prone to electrolytic failures in the PSU (as they fitted known sub-standard ones) - this commonly trashes the EEPROM in the set - so this could easily be the problem. As it's not consistent on different screens, it's highly unlikely to be the LCD or T-CON.

First look for bulging electrolytic's in the PSU - if they are bulging, then they are faulty. If they aren't bulging, they could still easily be faulty, and would require testing with an ESR meter. If you don't have an ESR meter then change them all for 105 degree, low ESR, high quality ones (I like Panasonic ones).

Next replace the EEPROM, fitting a new blank one 'should' prompt the set to load it with the original factory settings - but you'll probably still need to go through all the service settings to set it up correctly.
 
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