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There are threads on here about black level tweaks on both LG and Samsung, so it's time for Panasonic to get tweaked.


I'm the owner of two Panasonic PZ80 series 1080p plasma TVs. One 42", one 46". They're pretty old TVs, I bought them both faulty, and they were easy to fix. One had a loose LVDS cable (between the A & D boards.) The other had a few cold solder joints on the PSU. Both work great now, they only cost me £140 total, so all in all, pretty good bargain. They're going in the new student house (I'm sure the flat mates will be pleased...)


Anyway, since I can't help myself, I decided to "mod" my plasma because being a 2008 panel, it hasn't got the best black levels (mind you, still better than a new LCD.) The colours and overall look of the panel are fantastic, it's just the black level that lets them down.


So, the factory settings were:


Vsus = 204.5V, Ve = 156.5V, Vad = -140.0V


I tweaked these to:


Vsus = 209.5V, Ve = 136.0V, Vad = -126.0V


You can see a video here of the tweak

http://www.youtube.com/watch?v=h_XglqNHuic


I did NOT touch Vda. (Never touch Vda or panel damage could result.)


I was able to get to Vad = -120.0V and get an even darker black level, however I got a lot of IR and dead pixels. Increasing Vsus helped get rid of some of those, but I decided to up the Vad to make the panel more stable. With these settings I have two stubborn dark pixels on the edges of the panel, but they don't bother me at all.


Unlike what others suggest decreasing Vsus (Vs on LG/Samsung) -does not- reduce the black level. The Vsus must be increased to supply more energy to the cells in the panel as lowering the Vad and Ve reduces the priming energy, making any particular pixel more likely to misfire (usually stay off when it should be on.)


The panel black level is now much darker. It's hard to tell by eye, but it looks to be around half to a quarter the original black level, of course visual comparison can be difficult, though I do have the 46" to compare it against which I have not yet modded.


This black level tweak firmly puts it in G10 territory, possibly a little better.


The 42" has about 7000 hours on it, the 46" has about 4400, I have a feeling these settings are only possible once the panel has aged sufficiently.

Of course, beware, high voltage and all that, and you could blow up something, there's always that risk, so take care, but if you're feeling a little dissatisfied, try this. It can breathe life into an old panel. I accept no responsibility for damage done, it's done at your own risk.
 
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