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Discussion Starter #1 (Edited)
SANYO DP50749 artifact issue. most parts inside are made by LG. I will take a video or photos and post on here. but its almost like things are bleeding over to the right hand side of things. like when i have no input hooked up it says no input found and it flashes around the screen and you can see a trail off to the right hand side of it. also when you watching a movie you see them off the right hand side of things. I already looked over the power boards and all caps and solder joints look good. I am wondering if its the logic board or what. i also hear a sound coming from the ysus. like a high voltage sound but not sure if thats normal for that part or not. its not that notisable unless your or lissening for it.




 

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Could be that the panel drive waveforms need alignment. I am not sure if you can align this one or not. If so, it will require a scope and the service documentation. Some sets have no adjustability and you have to change boards and/or panels if there is a problem.
 

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Discussion Starter #3
I don't know anything about ajusting that. I dont have a scope. Tv is a 2009 model and was a customer store return. None of the boards even show any burn in hot spots. Do you know what board would control this issue? I see lots of boards for this model on ebay. It's not just whites that bleed over its all colors. It seams like it gets lines of colors off to the right hand side of things.
 

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Discussion Starter #4
I just looked at it again. its only lighter colors that bleed over to the right. and they are lines that go up and down.
 

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Discussion Starter #5
I was on ebay and looking at logic boards. mine has a led light on it that flashes and goes out flashes and goes out. the one on ebay says "Light Solid Green" is it to flash or is it flashing because it's bad?
 

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I do not know. I would have to get a service and/or training manual and see if it is documented. Typically, with PDPs, this is related to the panel drive, but it could be a problem at the processing level as well.
 

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There are lots of sources for manuals. Some are listed in the vendor listings and some in the stickies in the Service & Support forums.

I doubt that you will find much info online for Sanyo. They have been a minor player in the PDP market and it is not a commonly discussed product. I do not recall what kind of alignments they had on this model and would have to do some research to comment any more.
 

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Discussion Starter #9
I was checking and LG model 50PQ30 uses the same boards. logic, ysus, zsus, power supply, upper and lower driver boards. not sure if its easyer to find info on the LG model or not. It looks like the only thing thats not the same is the main motherboard/input board.

some places list the model number as LG50PQ30
 

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The good news is that the LG boards typically have extensive adjustments available to deal with "mal-discharge" which is my guess that you are seeing. The bad news is that this is not a DIY set of alignments, beyond maybe setting the panel d.c. voltages. The details are provided only in the LG training courses and related manuals, which are not public. The alignments require a good scope, along with an understanding of how to use it and how plasma panels work, as well as the details of the panel waveform specifications. You need to get the unit to a trained LG tech. Changing boards may be fruitless unless it happens to be a video processing artifact on the main board.
 

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Discussion Starter #11
When i look at the boards i don't see any adjustments on the zsus, but see 4 adjustable resisters on the ysus. It looks to be the only board with ajustments. This is also the board i hear a high voltage sound coming from. I am thinking this board may have an issue besides just an ajustment. I called sanyo to see if they have any info on this issue. they were able to tell me the tv was returned to a walmart in November 23rd of 2009. They have a 90 day warranty that people can take tv's back to the store for an exchange. then after that its a 1 year warranty. since i bought the tv as is it doesn't have a warranty. I am not sure how long until someone started to have an issue. I don't see how the adjustments would get out of alignment that soon. I am thinking its more of a board issue. Moving the adjustments didn't make it get any worse or better.

I moved the adjustable resisters a little after marking were they pointed ( I used a marker to mark were they lined) and they don't ajust my issue one makes the screen brighter. one makes the screen get red pixel spots, the other two i didn't see any changes when moving them slowly.
 

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I understand the desire to find a solution, but I must warn against adjusting things without the right documentation and equipment unless you know what you are doing and are sure that it will not create a problem. These adjustments can be very critical and a little off can compromise the life of the ysus IPM, the buffers, or the panel, not to mention have unintended consequences for the image such as increased image retention, gamma issues, gray scale linearity, or mal-discharge.
 

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Discussion Starter #13
Good news! I ordered the logic board off of ebay for 25 dollars shipped and the tv works great. The issue was the logic board. I went a head and ordered the stock remote to go with the tv at the same time i ordered the logic board. most places wanted 54 or 45 dollars for the remote but i found one for 25 plus 5 dollars shipping. It came today too. I am giving it time for a burn in test before i put it back together but it's working good right now.
 

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Discussion Starter #14
It's still working good. Not that hard of a repair. If any of you see this happening in your set you may want to give the logic controler board a try.
 

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Discussion Starter #15
Tv is still working great with no issues. I was afraid that maybe the board would go out again if something in the tv made it go bad. I guess it just had a bad board from the factory.
 

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Discussion Starter #16
I just received this tv back today and it doesn't display an image on the screen. when power button is hit you can see the screen go to light up then goes dark. the person said they still had audio. When tv is on the logic board is flashing a green led 3 times quickly then one time longer. Anyone know what that code means?
 
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