Panasonic plasma horizontal lines

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  • tom66
    EVs Rule
    • Apr 2011
    • 32560
    • UK

    #1

    Panasonic plasma horizontal lines

    Panasonic plasma TH-42PZ70BA. Full HD 1080p 42" set.

    I fixed a Y-sustain (SC board) issue in this TV preventing power up (6 blinks - energy recovery SOS. Turned out to be a shorted MOSFET.) However to get the Y-sustain out I had to remove the buffers. After assembling it all I've now got a good picture, apart from varying width horizontal lines across the screen and even or odd fields from each block missing on some bars.

    I was able to, with a lot of coercing and careful screwdriver tapping near the connectors, to get the display mostly okay on the bottom side, but a few lines still exist... and the top side is very bad still as I haven't attempted that. I've tried some contact cleaner too, that seemed to help.

    So, is there a better way to go about this?

    I'll post pictures tomorrow if needed.
    Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
    For service manual, schematic, boardview (board view), datasheet, cad - use our search.
  • tw2005
    Badcaps Legend
    • Oct 2011
    • 6458
    • Australia

    #2
    Re: Panasonic plasma horizontal lines

    Originally posted by tom66
    Panasonic plasma TH-42PZ70BA. Full HD 1080p 42" set.

    I fixed a Y-sustain (SC board) issue in this TV preventing power up (6 blinks - energy recovery SOS. Turned out to be a shorted MOSFET.) However to get the Y-sustain out I had to remove the buffers. After assembling it all I've now got a good picture, apart from varying width horizontal lines across the screen and even or odd fields from each block missing on some bars.

    I was able to, with a lot of coercing and careful screwdriver tapping near the connectors, to get the display mostly okay on the bottom side, but a few lines still exist... and the top side is very bad still as I haven't attempted that. I've tried some contact cleaner too, that seemed to help.

    So, is there a better way to go about this?

    I'll post pictures tomorrow if needed.


    I had a similar issue when i worked on a TH-42PX7A. The y-buffers had been played with. It took me about 3 goes to figure it out. All i remember is although they appeared to be seated corectly they were not. the clue I got was the locking levers were raised ever so slightly as the ribbon had not fully gone in and seated. when i got it right you could feel them click in just that little bit further and the tabs were easier and fitted totally flush.

    Comment

    • tom66
      EVs Rule
      • Apr 2011
      • 32560
      • UK

      #3
      Re: Panasonic plasma horizontal lines

      Originally posted by tw2005
      I had a similar issue when i worked on a TH-42PX7A. The y-buffers had been played with. It took me about 3 goes to figure it out. All i remember is although they appeared to be seated corectly they were not. the clue I got was the locking levers were raised ever so slightly as the ribbon had not fully gone in and seated. when i got it right you could feel them click in just that little bit further and the tabs were easier and fitted totally flush.
      Thanks for your help - using your method I was able to get the picture perfect. Thanks!
      Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
      For service manual, schematic, boardview (board view), datasheet, cad - use our search.

      Comment

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