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Possible to fix color blobs?

post #1 of 13
Thread Starter 
So, I've seen some people here have pink blobs (currently my set does) or green blobs, or such. I'm asking Sir tom669 to shed some light on the issue. Sir, could you please explain under diffusion, and what exactly is VSUS voltage? I noticed in the service menu there is a VSUS configuration of HIGH and LOW, and a test pattern for it. Could you go into a little detail, and possibly beyond service menu?

Thank you, Sir!
post #2 of 13
If this is one of these newer Panasonic plasmas, you need to see what the current VSUS setting is (HIGH or LOW) from service menu. The plasma panel is made very precisely by Panasonic so only two voltage settings are usually necessary. If yours is currently LOW, set it to HIGH. This may sort the problem out. If it is currently set to HIGH, or changing it does not work, then the cover will need to be removed to make adjustments to the VSUS and VE.

VSUS is used to make the image appear on the plasma panel. If the gas does not discharge properly into plasma you get excessive UV light, leading to purple/pink tints to the image. The gas discharge probability is determined by the panel pressure, which is very dependent on manufacturing tolerances. Small tolerance differences lead to panel variations, which is why there are multiple settings. Old plasma panels used to have six different fully variable voltages to adjust; trying to adjust those was... "fun", if it could be put that way.
post #3 of 13
Thread Starter 
I changed it, it's still there. So I'd have to open the panel and adjust make further adjustments? That's something I may be interested in after my 30 day return policy is up, if I end up keeping the TV. For future reference, could you explain how to do it?

Of course, I also take full responsibility of any actions I decide to do. I don't mind doing work, I just need to know how. It can't be much worse than working on a CRT.
post #4 of 13
Plasma displays use a much lower voltage than a CRT (200V Vsus vs. 30kV final anode); however they are still perfectly capable of permanently terminating your heartbeat if you are not careful.

As for fixing it, you will need a digital multimeter. You need to find the VSUS test point and trim pot and adjust that to the panel spec, usually hand written by the engineer who tested your panel. Then find the VE test point and trim pot, and adjust that to spec. If the picture still appears poor, the VSUS may need to be increased beyond nominal rating, though the maximum limit of 210V should typically be observed, depending on panel technology. I'd not generally go higher than 5V from the panel spec.
post #5 of 13
Thread Starter 
Quote:
Originally Posted by tom669 View Post

Plasma displays use a much lower voltage than a CRT (200V Vsus vs. 30kV final anode); however they are still perfectly capable of permanently terminating your heartbeat if you are not careful.

As for fixing it, you will need a digital multimeter. You need to find the VSUS test point and trim pot and adjust that to the panel spec, usually hand written by the engineer who tested your panel. Then find the VE test point and trim pot, and adjust that to spec. If the picture still appears poor, the VSUS may need to be increased beyond nominal rating, though the maximum limit of 210V should typically be observed, depending on panel technology. I'd not generally go higher than 5V from the panel spec.

That seems very easy to do. I'll have to get a multimeter because someone stole my old one. I'm surprised no one has asked this before, considering I've seen talk of people having service techs come out to look at it but not getting it done because screen uniformity it isn't covered under warranty.
post #6 of 13
...but it should be. It's even specified as a malfunction in several Panasonic service guides that I have seen and used before.
post #7 of 13
I just want to thank tom669 (and God) on this VSUS fix. I recently bought a Panasonic UT50 55inch Plasma online and i love the TV (coming from my old G10 Plasma) but this new UT50 i noticed had pink/yellowish blob on the right hand screen that i noticed about two weeks after getting this new TV and it has been bugging me so much because i felt inside that the problem would only get worse after reading other stories.

Anyways..what i did was go into the Service Menu and messed around with some settings with no avail and my 30 days for full return/exchange is coming up in a few days ...i really didnt want to go through the hassle of having to return it so i figured i would do one last good few hours of online research trying to find a fix for this nasty yellow/pink blob that sticks out like a soar thumb expecially on white images or white websites (i use my tv for internet as well) ...i was about to lay it down for the night and i just ran into this thread via google and low and behold..i tried the VSUS fix and it worked!! The nasty yellow blob/pink hue blob went away..just like that! It was getting so bad that i was getting burn in from the yellowish color onto my panel at times when i was on white background websites...soon as i made the VSUS i instantly noticed the difference!!

By the way..my tv had it set on LOW for VSUS ..it is now on HIGH which did the trick!! It was very bad on the far right side of my screen..when i would scroll through a webiste like avs forums..as i scrolled down i could see the white turn into a yellowish/pinkish blob on the right side on light or white backgrounds...now its gone..all whites are now even in color.

Thank you and thank God! I even said a prayer for this fix to work before i did it hehe
Edited by Moegames - 10/14/13 at 8:35pm
post #8 of 13
Quote:
Originally Posted by tom669 View Post

If this is one of these newer Panasonic plasmas, you need to see what the current VSUS setting is (HIGH or LOW) from service menu. The plasma panel is made very precisely by Panasonic so only two voltage settings are usually necessary. If yours is currently LOW, set it to HIGH. This may sort the problem out. If changing it does not work, then the cover will need to be removed to make adjustments to the VSUS and VE.

I'm having problems w/ my 55GT30 and tnx to tom669, I went into the SM and saw that VSUS was set to LOW. So I changed it to HIGH and it's almost perfect, much better than it was. So maybe a manual adjustment will make it perfect.

Tom669, would you comment in my thread . . . here ? I have the SU, SD and SC boards that I can replace.

Again tnx for your expertise! smile.gifsmile.gif
post #9 of 13
I also found that my VSUS setting was "LOW" and set it to "HIGH". That seemed to solve the problem about 95% improvement.

Today, I checked it and it was fine; about 9 hours later, I turned the set on and after about 20 secs, the set turned off! mad.gif

Got the "7" blinks and that means the "SC" board (and maybe the SU and SD buffer boards) has failed. As I related, it has been going bad and it finally went. I would say that the VSUS voltage setting changed to HIGH urged it to fail.

I have the replacement boards, so in the next few days, I'll get it repaired.

The point here is to be mindful that there could be consequences to setting VSUS to "HIGH"! eek.gif
post #10 of 13
Higher VSUS will lead to higher power dissipation in the panel and SC board, but only by a few percent. Realistically you might be taking 1,000 hours off the 25,000 hour lifespan of the SC.
post #11 of 13
I successfully fixed my P55GT30 today. Details for those who may be interested are here.

Also returned the VSUS setting to "LOW" since the additional voltage is not needed with the new SC board. Also LOW is the factory default.
post #12 of 13
What's the procedure to adjust VSUS? How can I get that information? I have a pink bloob right in the centre of the screen and a slightly blue oneon the right. The set is 50ST60E. Thank you!
post #13 of 13
I've change it to high and there's no improvement, the pink blob is there. It is supose to see the change imediately or it should fade away slowly?
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