LG 42sl8000 inverter noise?

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  • nackgr
    Member
    • Mar 2015
    • 18
    • greece
    #1

    LG 42sl8000 inverter noise?

    Hello

    I have this tv LG 42sl8000

    and both inverter boards do a buzzy noise ( the right it is louder)

    The board is 6632L-0574A

    http://www.ebay.com/itm/LG-INVERTE-B...gAAOxyJX1TCsfP


    The noise comes from the 2 inductors (yellow big with thermal pad on them ) (i am not sure how to call them)

    What should i do ?
    Should i replace them ?
    Any idea how to search them they say on them l2-cf42-b-09902A-K0
    Tags: None
    • dick_barton
      Badcaps Legend
      • Aug 2015
      • 6642
      • Wales
      #2
      Re: LG 42sl8000 inverter noise?

      I don't think there is a lot you can do other than ensure the solder joints are all good.

      The noise is probably due to the frequency of the driving signal in the coils vibrating the coils on the former on which they are wound.

      Someone else may have a solution.
      Willing to help but I'm no expert.

        Comment

        • Alastair E
          Chief Womble
          • Mar 2013
          • 1963
          • U.K.
          #3
          Re: LG 42sl8000 inverter noise?

          Only time Ive had Inverters squeek/whine is when a tube or two are duff.

          The LG type are wired in parallel and the reduced load--due to duff lamps upsets the drive from the inverters.

          Get set on a full-white screen from some source or other, computer maybe--look for darker bars in image...
          TELEFIX

          How PLASMA SCREENS WORK, X-SUS and Y-SUS what they do--
          http://www.irf.com/technical-info/appnotes/an-1088.pdf
          PLEASE DO NOT EMAIL ME PRIVATELY FOR REPAIR ADVICE. QUESTIONS BELONG ON THE FORUM!

            Comment

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