Plasm tv repair WARNING !!

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  • RCA2000
    Senior Member
    • Sep 2014
    • 111
    • USA

    #1

    Plasm tv repair WARNING !!

    I have been in this repair field for a long time--so I know of what I am speaking. Up till last year--I did this stuff every day. I was the "master tech", the one the "kids" (novice , young "techs", who did screenings and minor repairs) went to--when there was a problem. I also repaired boards--when this was possible--for the other techs then to use.

    I worked on a LOT of plasma sets. These really should be called "fluorescent tv" sets--since the phospor--NOT the plasma 9inoized gas) is what produces the picture--but I guess that would not "ring " right wiht the masses.

    Anyway--there is something everyone MUST be aware of--when replacing ANY PDP panel.

    YOU MUST DISCHARGE THE VS SUPPLY.... BEFORE INSTALLING THE ADDRESS LINES !!!!

    NO exceptions !! If you fail to discharge the VS supply on the power supply board, (usually around 60-75V), you run a HIGH risk--of blowing out one or emore driver chips on the address lines on the bottom of the panel.

    I HAVE seen this happen. The result is usually a column that is dead or full of "cross talk" (noise) and NOT useable. And one would NOT know--if it is a bad PDP--or one that was "blown out" by a loaded VS line..

    This comes directly from Samsung--BTW--in a training seminar I had.

    SO--take a resistor, of say 1K or so, and apply it to the VS out of the supply and ground and discharge for at LEAST 5 seconds--before connecting the address lines. (WITH the set unplugged--of course !!)


    This will protect those fragile address chips on the bottom ribbons--from getting killed by a surge.

    Also--NEVER--EVER-- operate the panel without the sink strap over the address chips at the bottom--even for a SECOND !! If you do--it WILL kill one or more chips... and the PDP panel I WATCHED a couple of 'techs" do this and ruin TWO panels this way !! They would NOT listen to me--when I warned them.

    Good troubleshooting..

    RCA2000--Jack S.
  • tw2005
    Badcaps Legend
    • Oct 2011
    • 6458
    • Australia

    #2
    Re: Plasm tv repair WARNING !!

    Originally posted by RCA2000
    I have been in this repair field for a long time--so I know of what I am speaking. Up till last year--I did this stuff every day. I was the "master tech", the one the "kids" (novice , young "techs", who did screenings and minor repairs) went to--when there was a problem. I also repaired boards--when this was possible--for the other techs then to use.

    I worked on a LOT of plasma sets. These really should be called "fluorescent tv" sets--since the phospor--NOT the plasma 9inoized gas) is what produces the picture--but I guess that would not "ring " right wiht the masses.

    Anyway--there is something everyone MUST be aware of--when replacing ANY PDP panel.

    YOU MUST DISCHARGE THE VS SUPPLY.... BEFORE INSTALLING THE ADDRESS LINES !!!!

    NO exceptions !! If you fail to discharge the VS supply on the power supply board, (usually around 60-75V), you run a HIGH risk--of blowing out one or emore driver chips on the address lines on the bottom of the panel.

    I HAVE seen this happen. The result is usually a column that is dead or full of "cross talk" (noise) and NOT useable. And one would NOT know--if it is a bad PDP--or one that was "blown out" by a loaded VS line..

    This comes directly from Samsung--BTW--in a training seminar I had.

    SO--take a resistor, of say 1K or so, and apply it to the VS out of the supply and ground and discharge for at LEAST 5 seconds--before connecting the address lines. (WITH the set unplugged--of course !!)


    This will protect those fragile address chips on the bottom ribbons--from getting killed by a surge.

    Also--NEVER--EVER-- operate the panel without the sink strap over the address chips at the bottom--even for a SECOND !! If you do--it WILL kill one or more chips... and the PDP panel I WATCHED a couple of 'techs" do this and ruin TWO panels this way !! They would NOT listen to me--when I warned them.

    Good troubleshooting..

    RCA2000--Jack S.
    Thanks for the tip and yes, I & suspect a few of us have inadvertently killed a panel doing this.

    The one I killed was also a Samsung. I powered it up forgetting the power lead to those address buffers you refer to.

    Connected and it arced as I did. Ended up with a dead ribbon, still hopeful it was not I ran the Tv gradually losing half the panel before I realised my next monumental stuff up.

    I had removed the long aluminium strip not realising it was in fact a heatsink.

    Yeah, TV was fixed , now junk.

    Fortunately with some of the Panasonics I look at, they have individual heatsinks integrated with the ribbons so lesschance of a fast burnout.

    Still, I often mention when disconnecting now any of the power from those buffers and sustains to let the voltage bleed off or better still, meter it first to make sure they're not hot from the caps holding charge.

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