Can you please help me find ground for this circuit?

Discussion in 'The Projects Forum' started by c627627, May 18, 2011.

  1. c627627

    Thread Starter New Member

    May 18, 2011
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    Long story short: Red Sparkling Dots on Plasma TV a.k.a Red Snow, kind of like "hell vision" may be caused by incorrect voltage if cause is not interference, cabling etc.

    After you open up the TV and read this: please click here

    If you want to check if Vsus is 193 Volts,


    You get the Service Manual. Locate the Test Point locations, please click here

    So now if you put the RED part of the Digital Multimeter on the Test Point, where does black go... where is ground for the circuit?


    • 1. Here is the Schematic, please click here

    • 2. For actual Pic of Plasma TV Schematic, please click here


    • 3. Is there ground next to TP15V, click here

    • 4. Overall view, please click here


    For additional info please click here. Thank you for your help.
     
    Last edited: May 18, 2011
  2. #12

    Expert

    Nov 30, 2010
    16,284
    6,797
    Pin 3 of SS11
     
  3. c627627

    Thread Starter New Member

    May 18, 2011
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  4. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Use the Mounting screws and pads for GND.
    It's right in front of u.
     
  5. c627627

    Thread Starter New Member

    May 18, 2011
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    When I attach the digital multimeter test probes like this: click here

    I get no change on the display: click here
     
  6. c627627

    Thread Starter New Member

    May 18, 2011
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    I just got it:

    When I make contact with RED to the green tip on the picture, I got a 15V reading and a 192V reading on the TPVSUS which means it's perfect, moving on to other test points.
     
  7. c627627

    Thread Starter New Member

    May 18, 2011
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    Results:

    I know it's not the cables because red snow appears with multiple inputs, even VGA input. It could be power related.


    Vset was 249V vs specs: 260V +/- 7V but I don't think it's that, there is no way to adjust that that I can see.


    Results here.
     
  8. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,754
    760
    You decided it is an adjustment fault that your set gives red snow.

    It faulted Just like that ?.
     
  9. c627627

    Thread Starter New Member

    May 18, 2011
    12
    0
    This is a problem that some Plasma TVs develop. Sometimes it's connections and power issues, but often the voltage is the problem. When the red snow issue is permanent, people didn't even measure voltage, they just adjusted the values until the red snow was gone.

    In my case I only have intermittent appearance of red snow flashing around. It happens with multiple connections so if voltage is not the issue - it may be a power issue or faulty board, I don't know.
     
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