ps43d450a2w screen issue

[comptek]

Hello everyone Happy New Year!!
i just picked this Samsung ps43d450a2w everything seems to be working just that after a few mins the screen slowly gets covered in red/blue dots then seems to get yellow patches on it, i have tested and reset VA VS & VSC voltages as per label on panel, also inspected and resoldered any dry joints on power supply and on y-sus that connects to buffer board...
any ideas please
Kind Regards

Gary

[sordids999]

Re: ps43d450a2w screen issue

Have u tried increasing VS by 4-5 volts to see if this helps

[comptek]

Re: ps43d450a2w screen issue

Have u tried increasing VS by 4-5 volts to see if this helps

yes i have just tried 4v then 5v and still the same any other suggestions ?
many thanks

[comptek]

Re: ps43d450a2w screen issue

also example if menu is on then closes tha image is still there for a while !

[comptek]

Re: ps43d450a2w screen issue

Well i think i have done it i tweaked vscan up a tad about 5v and its cleared will this cause a problem ???
i was wondering if it was a weak cap doing it ?

[Alastair E]

Re: ps43d450a2w screen issue

Doubt there'll be a problem--wont be a cap providing the voltage was right to start with--All you have done is compensated somewhat for old/aged panel. How long it'll last is anyones guess.

[comptek]

Re: ps43d450a2w screen issue

Doubt there'll be a problem--wont be a cap providing the voltage was right to start with--All you have done is compensated somewhat for old/aged panel. How long it'll last is anyones guess.

thanks Alastair its only just 4 yrs and 3 months old lol but hey ho!

[comptek]

Re: ps43d450a2w screen issue

well its still being a problem i have put all voltages back as they were and took a video,
when the voltages were tweaked up it worked fine and then when cold it was back so tweaked the vscan again and from cold perfect when it got hot it started to come back again
video below its like temp screen retension ?


https://www.youtube.com/watch?v=AY8MiMaQQvc

[comptek]

Re: ps43d450a2w screen issue

hi again
any suggestions please about above video image retension ?

regards
Gary

[ReeceyBurger123]

Re: ps43d450a2w screen issue

Im slightly baffled buddy, would need the set here with me. Maybe Xmain maybe firmware, have you tried firmware ?

[Alastair E]

Re: ps43d450a2w screen issue

Hmm....

Has the control-board ever been out/replaced?

Reason I ask is the temp of the panel is monitored by control-board and timings/etc altered to compensate for gas-pressure variations.
LG use a thermistor chip thermally coupled to the back of the panel by a dead-toad.

Sams I'm pretty sure do summit similar but how not off top of my head, sure...

[ReeceyBurger123]

Re: ps43d450a2w screen issue

With these sets Alastair im sure I read somewhere that the firmware doesnt clock the timings correctly and doesnt adjust to the proper drive methods for the panel but normally that causes pink banding so im unsure on this one.

[Moreno83]

Re: ps43d450a2w screen issue

Can you try a different image like normal instead of dynamic? This because your pushing the panel to the max on dynamic with contrast at 100%.

Try image setting on normal with a lower contrast , like 60/70.

Im curious if the same symptoms occur.

[Moreno83]

Re: ps43d450a2w screen issue

Im saying this because i get a little sparkles on my VT50 when i use dynamic with contrast 100 and brightness 60/70.

[comptek]

Re: ps43d450a2w screen issue

** Reece, i upgraded the firmware off of samsung site no difference,

** Alastair, no control board has not been changed, Yet lol, it happens from cold so could it be faulty ???

**Moreno83, i will try that cos im sure it made things worse when put on dynamic :/
thanks for your input guys

i was tinkering yesterday i used a hair dryer on the y-sus board i gently heated up the bit where the yellow transformer and it got worse put it cool and the picture reverted back to just being bad, it did make a differnce when vscn was tweaked up a bit but then started acting up when it was on for a while... so could this mean an issue on the y-sus ?