I have a Phillips 42PF320A/37 Plasma TV (Chassis # BP2.3U) that has a full screen picture and good sound but it has a red noise or flicker that is superimposed on the bottom half of the screen. (See Photo)
I have replaced Plasma TV circuit boards before but am not sure which to replace this time. I suspect the Main Logic board (LJ41-03387A) but I also am not sure about the Signal Processing board because it contains the VIPER circuitry.
Thanks in advance.
Have simular problem w/50pf7321d/37.
Red noise cloud on black parts in center of pic.
FiOS box switched out. Can turn color down,
set color to cool, brightness down way low or use ECO setting and get minor relief. But, that's a poor pic.
I'd replace board if I could figure which.
Panel replacement can't be found...
The old saying that a pictures is worth a thousand words could have been looking at this one... If the lower screen had been streaked in B&W or bands ran completely through the picture Old Drummer I would suspect the logic board also but that's lower y-board failure.
Bill
The lower Y is the buffer... On the upper Y or Y-Main, in the left corner of the board you have a grouping of little green pico fuses and one is usually open - - What's happened is that the regulator in that circuit has opened the fuse as it shorted. But the failure is usually a cascade one and there are several components, diodes, caps etc. that you'll find have also failed... Usually the caps will simply measure a high equivilent series resistance and the diodes will have some measurable leak. That's simply static testing with and ESR meter and a DMM..
In short, yes, I would suspect the Y-Main, I doubt the buffer is affected, but you might want to static test that also for good measure.
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Hi!
as i see your picture maybe that is lack of vertical sync or vertical
ramp... can you send me the service manual then i diagnose this
problem. send me at [email protected]
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This is the full screen picture (good sound) that has the red noise or flicker that is superimposed on the bottom half of the screen. (See Photo)
I do have the pdf Service Manual.
Problem has not been solved and I did NOT post that it was.
Sent the Service manual Nov. 11. The PDP does not have any integrated electronics. Any solution suggestions?
Sent the Service manual Nov. 9, still awaiting suggested solutions.
Hi Techman,
Here's a copy of the email I sent. Let me know if you have a problem downloading it.
Techman,
(You asked for the service manual for the subject TV. It is over 30, 000 KB and I don't believe it is easily downloaded on email so I ftp'd it to one of my web pages for you to download as a zip file. Go tohttp://www.radio4polkas.com/SM_pdf for the file. It'll take a while to download.
I did not believe the first solution was relevant since it appeared to be typical for a CRT TV not a plasma. I expect the problem is with the LVDS or the Display Ctrl which input to the PDP. I do have pertinent test equipment (oscilloscope, multimeter, etc.)
Thanks in advance.)
You are worthless. I have downloaded the file on three different computers with no problems and have not had a problem to un-zip it. As a result I have removed the file so others don't have a free service download.
I don't believe you have ever properly diagnosed a "Plasma" TV.
Just get me some help with someone with Plasma experience!
I assume the board you are referring to is the Y-main (LJ41-02759) not the Y Buffer (lower). The Phillips Service Manual refers to the Y-main as the "PDP Inverter". Can you suggest components to suspect or waveforms to check? I can email you my URL that has the pdf Service Manual.
When first turned on the picture flickers and the sound dissapears
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