Samsung Plasma - sparkles in one corner

[WVREDMAN]

Trying to trouble shoot a problem on a Samsung PN63A650T1 Plasma TV. In the attached picture you will see that the lower left corner has an issue.

I have take apart the TV and did the following tests.

1) replaced the G-Buffer board (swapped from the upper right corner)
2) replaced the main input board
3) took the ribbon from the upper left corner and ran to lower right corner (this would have told me it was the processor board)

The y-buffer board does not appear me to be bad because the whole half of the screen would be bad and not one third.

I am assuming that there is an issue with the actual plasma screen and it would not be worth fixing.

Can someone give me some help on a test procedure or if someone else has run into the same problem.

[tom66]

Re: Samsung Plasma - sparkles in one corner

Cannot see picture?

But, anyway, I would start with -Vsc/Vset adjustment, basically just tweak the pots (adjustments) slowly and watch the display. If it starts misfiring more, go the other way.

If that fails I'd look at Yfr then Yrr in same manner -- but display timings. Consider dropping Vs too.

[WVREDMAN]

Re: Samsung Plasma - sparkles in one corner

Well, I have tried various ways to upload the pic of the TV but it will not. Keeps saying invalid file.

[shovenose]

Re: Samsung Plasma - sparkles in one corner

Well, I have tried various ways to upload the pic of the TV but it will not. Keeps saying invalid file.

Yeah I have the same issue just use like imgur or something

[WVREDMAN]

Re: Samsung Plasma - sparkles in one corner

OK, I have removed the x-buffer low board from the TV and it appears to be this board that is bad. The TV is functioning the same as if the board in installed.

What should I be looking for to make sure it is not the x main board?

[tom66]

Re: Samsung Plasma - sparkles in one corner

Sparklies are not caused by the X buffer, and very very rarely by the X-main board. They are caused by Y-main voltage/timing, or power supply voltages being incorrect.

[WVREDMAN]

Re: Samsung Plasma - sparkles in one corner

Here is a link to my photos so that you can see what is happening.

The screen works perfect except for the lower left corner.

link to photos http://www.flickr.com/photos/1004476...th/9539476343/

[tom66]

Re: Samsung Plasma - sparkles in one corner

Oh, I totally misunderstood your problem. Unfortunately, that looks to me like a defective plasma panel, it would not be repairable. The driver chips bonded to the plasma glass have failed. Very small chance of D board fault, but the single pixel line makes me think dud panel.

[Ryu.Hayabusa]

Re: Samsung Plasma - sparkles in one corner

I was going to say it might be something on the logic side that is having a problem, but it's cutting off the OSD message on the display, so seems to me that it's something after the logic side of things. Might be an ADC? PWM Controller? MOSFET? Buffer board?

It appears to panelize out to 3 on top and 3 on the bottom if you were to copy/paste that square across the screen (without lens distortion), so maybe that will be a clue to looking for 6 identical parts.

Do the "static" and lines change each time you power it on? My Samsung plasma from 2007 (which I recently destroyed and repaird lol) had a ~3" vertical band with colored static/lines that would change each time I turned it on, but the band size stayed the same if I remember right. Not sure what the cause was as I returned it for a replacement but it also would "overlay" the OSD.

Does this occur on all inputs? Have you tried analog (VGA, Composite, Component) versus digital (HDMI, DVI) to see if it makes any difference?