Plasma Pixelization SAMSUNG PS50B430

[ReeceyBurger123]

Re: Plasma Pixelization SAMSUNG PS50B430

Im quite sure you Xmain is the fault, as its nothing obvious have you got a scope to check the output of it ?

[creatou]

Re: Plasma Pixelization SAMSUNG PS50B430

Yes I have a scope. Wich waveform must be present? I have checked all the igbt, mosfet and diodes present on the heatsink one by one. All are OK

[tn245]

Re: Plasma Pixelization SAMSUNG PS50B430

I've currently got two of these open. One with a control board issue causing regular vertical lines across the screen, the other I bought as a "fully working" TV because someone was selling it cheap. Both of them with good control board in have a picture approaching what your photos show. Speckly mist, especially noticable on solid areas of green. They have big trouble with the "The Following Preview Has Been Approved For All Audiences" green splash screen before a trailer. Also some speckling in gradations of skin tone.

Have checked voltages and reflowed joints with no effect. I'm thinking it's just crappy samsung plasmas and panel aging. I've worked on samsung panels in the past with similar maldischarge which I could never resolve completely. It gets better as the TV warms up and is perfectly watchable from normal viewing distance. There's also quite a bit of red sparkles when turned on from cold.

Can you tell me how you get the firmware update on this TV? Can't find anything on google about how to do it. Will also try playing with voltages and timings after that to see what I can improve.

[ducky29]

Re: Plasma Pixelization SAMSUNG PS50B430

Please post a picture of the sticker on the back of your TV

[tn245]

Re: Plasma Pixelization SAMSUNG PS50B430

Please post a picture of the sticker on the back of your TV

Yes, here are some pics. In fact one of them is a PS50B451, but both use the same S50HW-YB05 panel and identical boards.

[ducky29]

Re: Plasma Pixelization SAMSUNG PS50B430

If the VS and Va voltages match to the values printed on the board you should replace YSUS board

[ReeceyBurger123]

Re: Plasma Pixelization SAMSUNG PS50B430

If the VS and Va voltages match to the values printed on the board you should replace YSUS board

Doesn't make sence to me, what about testing the drive voltages generated by the Ysus to make sure its working or not rather than thorwing boards into it.

[tn245]

Re: Plasma Pixelization SAMSUNG PS50B430

Doesn't make sence to me, what about testing the drive voltages generated by the Ysus to make sure its working or not rather than thorwing boards into it.

Yeah, I was going to say, seriously? Ysus bad on both TVs? Voltages are spot-on to spec on panel sticker. I'm going to play with some adjustments later to see if I can improve things at all.

Still haven't found out how to update firmware. Can anyone enlighten me?

[ReeceyBurger123]

Re: Plasma Pixelization SAMSUNG PS50B430

What about Ve whats that up to ? Might be best just to have a play see what you can do.

[tn245]

Re: Plasma Pixelization SAMSUNG PS50B430

Just been working on the B451. Ve was in spec. I had a play with voltages. Upping Vs and -Vsc improved things a lot. Then I finally figured out my way around the Samsung website and did the firmware upgrade and it got way worse. So I put the voltages back where they were and it's pretty good now. A bit of faint image retention and the green trailer screen still doesn't look solid color but normal scenes are very watchable. So just panel aging which the firmware adjusted for it seems.

[chrismurphy]

Re: Plasma Pixelization SAMSUNG PS50B430

do not increase VS reduce it slightly this will improve an aging screen