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VT50 yellow-ish blob on display - Page 8

post #211 of 964
Quote:
Originally Posted by chadwick537 View Post

Haha, I could've been a little more clear. Yes, we toggled to High VSUS and calibrated to 218v thinking it would be within spec and no side-effects. Toggled to Low VSUS without adjusting any trimpots and got 210v. Recorded the +/- 8v difference between the two and then set the VSUS to high. Honestly, we couldn't see the blobs at either low or high VSUS (210v vs. 218v) and weren't getting any adverse effects (blue speckles) so we closed it up and put it back on the wall. I initially left the VSUS at high (218v) but I was able to produce some blue speckles the next day so I switched it to low VSUS (210v) and haven't had any blue speckles since -- and no blobs.

I think (my blobs at least) were a combination of a couple different things -- even on high VSUS before we calibrated, I had readings of 209v and 199v -- both below panel spec. Turning these up/down even without measuring voltages you could see the difference in screen uniformity (bigger blobs, smaller blobs, no blobs, etc.) but it wasn't until I had them both at the same voltage (ie. 205v each, 210v each, 218v each) that the picture looked uniform. Perhaps my set has another issue with the blue speckles at higher voltages, but I have no way of testing that without another 65VT50.

Hopefully that is a little more clear!

Very clear! And when will you be in Dallas to adjust my VT50? I missed that part wink.gif
post #212 of 964
It's really very easy to do! You just need a multi-meter, screwdriver and some time =D

I can walk you through it if you decide to do it -- just let me know!
post #213 of 964
Quote:
Originally Posted by chadwick537 View Post

It's really very easy to do! You just need a multi-meter, screwdriver and some time =D

I can walk you through it if you decide to do it -- just let me know!

I may do that after the warranty runs out and if I haven't received a replacement from Panasonic. Thanks!
post #214 of 964
What is a multi-meter?
post #215 of 964
A digital multimeter -- Amazon has them for sale -- just used to take voltage measurements in this case.
post #216 of 964
Quote:
Originally Posted by JimP View Post

Bill,

Here's a few different ones. You do want to be sure that it's a low impedance digital multimeter.

http://www.tigerdirect.com/applications/SearchTools/search.asp?keywords=multimeter

On the contrary -- you want a high impedance one. Virtually all are. The same meter TigerDirect sells for $20 can be purchased for under $5 from eBay.
post #217 of 964
Hell, I wouldn't know where to place the thing for measurements
post #218 of 964
I'm sure Chad will gladly direct you to the relevant points on the circuit boards.

Chad: You're sure these pots are found only on the GT and VT series? I can't remember seeing pots on my UT50 when I had the back cover off to single out where my buzzing was originating from. Then again, I never specifically looked for any pots and I could have overlooked them.
post #219 of 964
The pots usually have gobbed glue on them to keep them in the factory position, which was set incorrectly.
post #220 of 964
In my case, all 3 of my pots (VSUS L/R and VDA) had no glue on them, nor did they look like they had ever had any. From my limited research, it looks like the 65GT and 65VT series are the only two TVs that have (2) VSUS trimpots -- any smaller or "lesser" models will just have (1) VSUS trimpot. As I noted, my display looked a lot better when the (2) VSUS trimpots were set to the same voltage. That probably wouldn't be an issue with the other sets that only have (1) trimpot. I'd assume simply adjusting the single trimpot to a higher VSUS setting would eliminate a lot of the blobs.
Edited by chadwick537 - 7/19/13 at 7:30am
post #221 of 964
Did you have VDA or VAD on your power board? VDA or VAD on your SC?
post #222 of 964
The 65VT50 has VDA on the power board (the trimpot) and it goes to the C boards at the bottom. I didn't see any other trimpots on any other boards. I believe in my reading there is VSUS, VAD and F15V that drives the panel.
post #223 of 964
Well, its been a week since the service tech looked at my VT50 and said Panasonic would call me in a couple of days. I haven't heard from Panasonic at all, so I called them today for an update and they told me there hasn't been any activity on the case yet. I was told my case has been escalated and that I should hear from them in another 48 hours. Why do I feel like I'm getting the run around?
post #224 of 964
Quote:
Originally Posted by DirtyWolverine View Post

Well, its been a week since the service tech looked at my VT50 and said Panasonic would call me in a couple of days. I haven't heard from Panasonic at all, so I called them today for an update and they told me there hasn't been any activity on the case yet. I was told my case has been escalated and that I should hear from them in another 48 hours. Why do I feel like I'm getting the run around?

Hoping you'll "give up" perhaps? I know you won't let them off the hook, and we're all hoping you get your desired outcome.
post #225 of 964
Haha, no I won't be giving up. I noticed a purple line on the left side of my screen in addition to the green one that the tech pointed out. I read online that this may be a sign that the panel is going. So, there's too much wrong with the TV to let it go at this point. As I said before, I'll post updates when I get them. In the meantime, everyone here might want to look to see if there's any colored lines on their panel as well. It would be the last vertical column of pixels on each side of the screen. I hope this is just my TV and unrelated to the yellow blobs.
post #226 of 964
Quote:
Originally Posted by damag0r View Post

Woah, I'm having a very similar problem with my July 2012 build UT50.

It's less than a year old so I'm getting it serviced.

It was very hard to get good pictures of it, but since the repair place asked me to I tried and tried until I was able to get a couple of pictures where it was visible and then I increased the color saturation until it looked a bit worse than it would even in person.

I assumed it was a panel defect and not something which could possibly be fixed by adjusting some pots. Still think it could very well be a panel defect.

Here's those pics of it:

http://imgur.com/Vpx8Yp5,AxDCAtp#1

Center is pinkish and the sides are greenish, it's especially noticeable when stuff moves through the green blob on the right of the screen.

When I first got the TV I noticed a strange green blob that was only visible when using the scrolling bar utility, but this disappeared after 80 hours or so of use so I forgot about it and didn't worry. Then at around 2000 hours or so I started noticing these new blobs... the pinkish splotch is about exactly where the green blob originally was if I remember correctly. At first it wasn't very noticeable, but now it's like there is no white on my screen especially when the ABL kicks in. If it's a view of the sky the clouds in the middle look pinkish and the ones on the edges of the screen look green.

PS. So does changing the VSUS setting affect how much/often the ABL kicks in? I'd like to reduce the amount ABL is used as much as possible without melting my panel from overheating. I hate ABL frown.gif

Getting boards replaced on Friday. I'll let you guys know if this fixes my very similar issue on my UT50.
post #227 of 964
VSUS has NOTHING to do with ABL and won't change that at all. ABL is affected by the eco energy-saving modes of these TVs, the only way to reduce it is to drop the brightness below the ABL point which would result in a significant brightness fall.
post #228 of 964
Quote:
Originally Posted by tom669 View Post

VSUS has NOTHING to do with ABL and won't change that at all. ABL is affected by the eco energy-saving modes of these TVs, the only way to reduce it is to drop the brightness below the ABL point which would result in a significant brightness fall.

What does the VSUS setting do exactly then?

Would it be theoretically possible to modify the board and/or firmware to effectively disable ABL?
post #229 of 964
VSUS adjusts the Sustain Voltage. The sustain voltage is used to make the image appear on the screen after it is programmed in by the address drivers (VDA on address driver plus VAD, VSCN on scan driver and VE on sustain driver). The other four aren't adjustable on modern panels, so the only one you can play with is VSUS. Increasing VSUS puts more energy into the panel, which can help the discharge improve resulting in a more even image.

Disabling ABL would result in one of the following: pink tint / maldischarge on brighter scenes, shutting down/SOS-error on bright scenes, destruction of power supply, scan driver, sustain driver, blown fuses, or cracked plasma panel.

I would therefore guess Panasonic would not make it easy to override any ABL option.
post #230 of 964
Quote:
Originally Posted by tom669 View Post

VSUS adjusts the Sustain Voltage. The sustain voltage is used to make the image appear on the screen after it is programmed in by the address drivers (VDA on address driver plus VAD, VSCN on scan driver and VE on sustain driver). The other four aren't adjustable on modern panels, so the only one you can play with is VSUS. Increasing VSUS puts more energy into the panel, which can help the discharge improve resulting in a more even image.

Disabling ABL would result in one of the following: pink tint / maldischarge on brighter scenes, shutting down/SOS-error on bright scenes, destruction of power supply, scan driver, sustain driver, blown fuses, or cracked plasma panel.

I would therefore guess Panasonic would not make it easy to override any ABL option.

Hi Tom, what does The VDA pot do. Why do you think the VT50 has it there for adjustment? You have mentioned it can do damage and is a risky one.
post #231 of 964
It adjusts the addressing voltage, which is used to program the image onto the panel. There are chips on the bottom of the plasma panel with around 384 outputs a piece, for a 1920 x RGB panel there are 15 drivers. If the VDA is increased too high, the drivers can fail, leading to stuck lines, black bars or complete failure to power up, which will be an unrepairable fault, due the drivers being bonded to the plasma display panel.

I expect VDA will have the same effect as VAD/VSCN adjustment, so adjust them instead. I've never played with VDA, because I don't plan on ruining a panel... maybe if I get one which is 480p or already broken I'll give it a go...
post #232 of 964
Thanks Tom. The reason I ask is that I opened up the panel to do the Vsus after Chadwick had led the way. I could see Vda there but stayed well away from it based on your warnings. Here are my observations:

Thanks Chadwick for the advice on how to safely open it up and the photos you have posted really helped.

My readings in Vsus low were Right 197V and left 203V. On Vsus high they were 204 and 210. If I increased Vsus left beyond this point I made the blue speckles so I left it at 210V. I could see it when I changed input on the screen where the letters HDMI would stay on the screen for a few seconds. I then adjusted Vsus right up to 210V and the panel filled out nicely. It looks like matching them works just like Chadwick said. No more yellow blobs.

I noticed no other pots in there other than Vsus left and right and Vad. Here is a photo of the Vsus right pot.



Thanks for all the advice. This forum and members are great in helping out.
post #233 of 964
Quote:
Originally Posted by Crudesinger View Post

Thanks Tom. The reason I ask is that I opened up the panel to do the Vsus after Chadwick had led the way. I could see Vda there but stayed well away from it based on your warnings. Here are my observations:

Thanks Chadwick for the advice on how to safely open it up and the photos you have posted really helped.

My readings in Vsus low were Right 197V and left 203V. On Vsus high they were 204 and 210. If I increased Vsus left beyond this point I made the blue speckles so I left it at 210V. I could see it when I changed input on the screen where the letters HDMI would stay on the screen for a few seconds. I then adjusted Vsus right up to 210V and the panel filled out nicely. It looks like matching them works just like Chadwick said. No more yellow blobs.

I noticed no other pots in there other than Vsus left and right and Vad. Here is a photo of the Vsus right pot.



Thanks for all the advice. This forum and members are great in helping out.

I may be next! So, with both VSUS pots at 210, did you leave the VSUS on High or Low when all was said and done? Or dose it no longer make a difference?
post #234 of 964
Quote:
Originally Posted by scirica View Post

I may be next! So, with both VSUS pots at 210, did you leave the VSUS on High or Low when all was said and done? Or dose it no longer make a difference?

Hi, I left it at high. I did this a bit of protection. This way I can't adjust it up any more from my service menu. I don't think it matters. I am just thinking that as the TV ages it may go through more voltage changes on its own. This way it gives me headroom to adjust it down in the future.

I have over 2000 hrs on it so it must have done this already to some extent which may explain the white blobs on dark screen turning up in the pro modes.

When I had the back off I took a look as to what might effect this. I noticed the position of the boards is perfectly matching my white patches. I tested a blank screen in the dark and the patches build up as the voltage builds up in the board. After it displays a white screen it takes a few seconds to build back up to full power.

These boards are also very close to the panel compared to the centre power board. Likely panasonic. This also happens to be the thinnest part of the panel to give it that cool design thin look end on. Maybe now too close and its without any shielding in behind. There is rubber shielding on the rear cover in these board positions but not on the metal panel side. I also noticed these white blobs do not go right to the edge. They only affect the panel up to the thin board next to it that is about an inch or so wide. This may well explain the darker band most see on the right hand edge of their panel. I can see it on mine also.



This means I can see no way of fixing these white blobs or any right hand of the screen band.The good thing is they seem to affect the pro mode less now with Vsus higher. This may be because the picture is a little brighter now. If there is any small amount of white on the dark screen it seems to drain these dark areas of their patches. It's only a problem now if the screen is very dark for quite a few seconds.

Thanks.
post #235 of 964
Quote:
Originally Posted by newfinator View Post

I have a VT50 which I've been enjoying since the summer but recently noticed that, while watching Hockey, I can see two small regions on the right and left edges of the screen that have a slight yellow or green tint to them. I probably would never have picked up on it if it weren't for that predominant white of the ice on the screen. It's actually fairly subtle and probably wouldn't translate in a photo but is hard to un-see once noticed. It somewhat reminds me of what my old projection TV looked like when it was on it's last legs. It certainly doesn't bother me as is but am concerned that it may be an indicator of things to come. Any ideas of what that might be?

Same issue was in my VT50, appears after 10 month in my house, panasonic upgrade my screen to VT60, free of charge smile.gif
Good luck.
post #236 of 964
Quote:
Originally Posted by Crudesinger View Post

Hi, I left it at high. I did this a bit of protection. This way I can't adjust it up any more from my service menu. I don't think it matters. I am just thinking that as the TV ages it may go through more voltage changes on its own. This way it gives me headroom to adjust it down in the future.

I have over 2000 hrs on it so it must have done this already to some extent which may explain the white blobs on dark screen turning up in the pro modes.

When I had the back off I took a look as to what might effect this. I noticed the position of the boards is perfectly matching my white patches. I tested a blank screen in the dark and the patches build up as the voltage builds up in the board. After it displays a white screen it takes a few seconds to build back up to full power.

These boards are also very close to the panel compared to the centre power board. Likely panasonic. This also happens to be the thinnest part of the panel to give it that cool design thin look end on. Maybe now too close and its without any shielding in behind. There is rubber shielding on the rear cover in these board positions but not on the metal panel side. I also noticed these white blobs do not go right to the edge. They only affect the panel up to the thin board next to it that is about an inch or so wide. This may well explain the darker band most see on the right hand edge of their panel. I can see it on mine also.



This means I can see no way of fixing these white blobs or any right hand of the screen band.The good thing is they seem to affect the pro mode less now with Vsus higher. This may be because the picture is a little brighter now. If there is any small amount of white on the dark screen it seems to drain these dark areas of their patches. It's only a problem now if the screen is very dark for quite a few seconds.

Thanks.
After looking at this picture and seeing where the boards are I can tell you that on both sides of the TV that the boards match up to exactly where I was seeing the blobs. And my blobs came out after watching TV for about 5 minutes. Enough time for the TV to heat up. Im not a scientist but when I had this issue I always though it was the heat from the TV in those areas that was causing the issue. When the tech put VSUS to high for me it really didnt do much either. But I didnt notice green blobs for the first few minutes my TV came on from a room temperature state. Really hoping when my replacement VT60 comes that this problem isnt a carry over.
post #237 of 964
Quote:
Originally Posted by damag0r View Post

Getting boards replaced on Friday. I'll let you guys know if this fixes my very similar issue on my UT50.

He replaced the boards and there was no improvement. He played with some of the trimpots and adjusted it so the peak brightness was a bit higher, but the green tinted edges and the red center is still very apparent. He took some pictures with his iphone to send to Panasonic, but considering how hard it was to get a good picture with a decent camera I somehow doubt he was able to get good pictures with his iphone. I'm going to be pretty pissed if I don't get a replacement panel or set to fix this issue. There are even visible changes in skin tone as someone walks across the screen. On white shirts and in clouds it's especially noticeable. I don't expect perfect uniformity, but the color is skewed WAY into the realm of visibility by the human eye and it's bugging me so much I can't even use the thing.

Again though I have a UT50, but the problem seems similar to what others are complaining in this thread, pink/green discolorations in the screen but I don't have "yellow" blobs.
post #238 of 964
They are obviously clueless it is sad if a knowledgeable forum member can figure it out why can't Panasonic ?
Edited by chunon - 7/30/13 at 12:38pm
post #239 of 964
VT60 came yesterday and everything seems to be perfect with the set. For now I do not see any blobs or color distortions. Will update further if I come across anything.
post #240 of 964
Quote:
Originally Posted by JKR1963 View Post

I just noticed two greenish blobs on my 60GT50 on Saturday............they were not there before. I bought the tv last July from Visions and I am not too happy after having a rising black G15.......and now possible problems with the GT50.

Panasonic Canada is giving me back my money, it is done via the dealer though, and I am paying extra to get a 65ZT60......will have it tomorrow at this time.
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