Plasma LG 50PT353 picture grainy

[bircaboy]

Please for some help.
My plasma suddenly have grainy picture. Which board should I look first?

[Andrew F. Ali]

Re: Plasma LG 50PT353 picture grainy

Are all your voltages Vs, Va, Vy, Vsc, Z-bias on the label correct? This looks like a bad Z-sus Bd.

[bircaboy]

Re: Plasma LG 50PT353 picture grainy

Andrew F. Ali, yes the voltages are correct. I changed with another working PSU, and measured with Fluke, all OK. I will buy ZSUS and we will see.
Thanx for your help.

[tom66]

Re: Plasma LG 50PT353 picture grainy

Before you buy Z-sustain how did you check Vzbias voltage??

[bircaboy]

Re: Plasma LG 50PT353 picture grainy

Tom66, please look at the attachments. Is this correct VBias measurements?
What are you suggesting me? Thanx for your help.

[Andrew F. Ali]

Re: Plasma LG 50PT353 picture grainy

Yes that is the Vzb 9Z-bias) test point.

[bircaboy]

Re: Plasma LG 50PT353 picture grainy

Should I adjust a little Vy,Vsc and Vzb?

[tom66]

Re: Plasma LG 50PT353 picture grainy

Were they within about 3 volts of the values on the sticker? If so, there is no need to adjust.

[bircaboy]

Re: Plasma LG 50PT353 picture grainy

Tom66, thanx for your answer. When the ZSUS board 'll come, I will report here.

[kiko1]

Re: Plasma LG 50PT353 picture grainy

try to resolder big coil on Z-sus board....

[bircaboy]

Re: Plasma LG 50PT353 picture grainy

Today I changed Z-sus, and the result is the same.
Any other suggestion?

[technium]

Re: Plasma LG 50PT353 picture grainy

did you find out what the promblem is?

[angelos]

Re: Plasma LG 50PT353 picture grainy

Nah, i think he sent that one to the landfill.