bypassing a backlight lcd bulb

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  • rivette65
    Member
    • May 2008
    • 12

    #1

    bypassing a backlight lcd bulb

    i have 10 Nec lc19m lcd monitors
    the problem is that the screen goes dim after 30s .and i found that in every one there is a bad backlight bulb : that's why it goes dim i
    i have tried to put an external bulb instead of the bad and the monitor does not go dim . and i have realise that with only one bulb the brightness of the monitor is good . so instead of changing a second new bulb i want to use only one . but the problem is the feedback circuit : with only one bulb the screen shuts down .
    ihave you any idea about what to connect in the bulb connector on the inverter to bypass the detection of the bulb or to bypass the feedback circuit
    thank you
  • alexanna
    Member
    • Mar 2010
    • 1346

    #2
    Re: bypassing a backlight lcd bulb

    Use the advanced search feature and type in [ backlight with a resistor]
    You will get some ideas.
    Al.
    Whatever I do, I consider it a success, if in the end I am breathing, seeing, feeling and hearing!

    Comment

    • rivette65
      Member
      • May 2008
      • 12

      #3
      Re: bypassing a backlight lcd bulb

      thank you Alexana . i will try to look for this solution
      . have a nice day

      Comment

      • Krankshaft
        Badcaps Legend
        • Jan 2007
        • 2328
        • USA

        #4
        Re: bypassing a backlight lcd bulb

        Rearrange ohms law if you know the bulbs voltage and current you can calculate the resistance.
        Elements of the past and the future combining to make something not quite as good as either.

        Comment

        • rivette65
          Member
          • May 2008
          • 12

          #5
          Re: bypassing a backlight lcd bulb

          hi
          i'm sure that there is a better solution ! i mean a modification at the primary ( before the high voltage) to disable the cut out . i have a tl494c on the board . have you any idea ?

          Comment

          • PlainBill
            Badcaps Legend
            • Feb 2009
            • 7034
            • USA

            #6
            Re: bypassing a backlight lcd bulb

            Originally posted by rivette65
            hi
            i'm sure that there is a better solution ! i mean a modification at the primary ( before the high voltage) to disable the cut out . i have a tl494c on the board . have you any idea ?
            Yes. I grew up on a farm. Farming equipment has shields to restrict access to rotating shafts, cutting blades, crushing bars, etc. Also you would find placards warning the user to turn off power before removing the shields. Many farmers ignored the warning. They were often known by nicknames such as 'Lefty', 'Three Finger', 'Thumbs', 'Peg Leg', 'Stumpy', etc.

            Safety features are installed for a reason. Disabling them is a stupid idea!

            PlainBill
            For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

            Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

            Comment

            • lucky13
              Badcaps Veteran
              • Aug 2007
              • 412

              #7
              Re: bypassing a backlight lcd bulb

              Once I left a good tube inside the monitor to bypass the bad lamp. So now there is light at the back of the monitor illuminating the wall a bit. It works OK.

              Comment

              • PlainBill
                Badcaps Legend
                • Feb 2009
                • 7034
                • USA

                #8
                Re: bypassing a backlight lcd bulb

                Originally posted by lucky13
                Once I left a good tube inside the monitor to bypass the bad lamp. So now there is light at the back of the monitor illuminating the wall a bit. It works OK.
                Ambilight!!
                For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                Comment

                • rivette65
                  Member
                  • May 2008
                  • 12

                  #9
                  Re: bypassing a backlight lcd bulb

                  thank you for your help
                  i have replaced all the backlights ! it was the best but not easy solution.

                  Comment

                  • lucky13
                    Badcaps Veteran
                    • Aug 2007
                    • 412

                    #10
                    Re: bypassing a backlight lcd bulb

                    Congrats rivette65! Good for you.

                    Comment

                    • rivette65
                      Member
                      • May 2008
                      • 12

                      #11
                      Re: bypassing a backlight lcd bulb

                      thanks Lucky13

                      Comment

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