Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Link

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  • spartantravis
    Member
    • Nov 2019
    • 17
    • Italy

    #1

    Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Link

    Hi guys

    I have a Technika 22inch tv that has an annoying flicker in the upper corner of the screen. I have figured out that one of the backlight strips is almost gone and is on its last stretch. This tv has 4 back light strips and I will still be able to use it with the other 3 backlights. The problem is the flicker as it is very difficult to watch/play with it.
    The inverter ( LK-IN220413) has 4 connections to the backlight strips. If I remove any one of them, the onboard mosfet detects it as a fault and switches off the entire backlight to protect the tv. A youtuber called MrReeceyburger123 produced a very nice video on the topic for this particular tv where he desolders a certain capacitor that prevents the board from switching off the backlight (link below)

    https://www.youtube.com/watch?v=yjiXmdU4dKs

    Unfortunately my tv uses a slightly different inverter board and with substantially more capacitors/mosfets on it. As I do not wish to randomly remove pieces of the board without knowing what is what, I wanted to ask you guys if you have any suggestions or guidelines on how to proceed.
    I can provide images of the board and part numbers but I cannot find anything useful on the internet about this circuit board apart from where to buy a new one.
  • dick_barton
    Badcaps Legend
    • Aug 2015
    • 6642
    • Wales

    #2
    Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

    At your own risk but here is a video
    Willing to help but I'm no expert.

    Comment

    • nomoresonys
      Badcaps Legend
      • Jan 2013
      • 12196
      • U.S.

      #3
      Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

      I wouldn't want to run a ccfl tv without protection circuit, could burn the house down.

      Comment

      • spartantravis
        Member
        • Nov 2019
        • 17
        • Italy

        #4
        Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

        Originally posted by dick_barton
        At your own risk but here is a video
        I already looked at that video. it is the link I used in the opening post. The inverter board is different on my particular model.

        Comment

        • R_J
          Badcaps Legend
          • Jun 2012
          • 9535
          • Canada

          #5
          Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

          look at the ic's datasheet and change or disable the protection

          Comment

          • spartantravis
            Member
            • Nov 2019
            • 17
            • Italy

            #6
            Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

            Originally posted by R_J
            look at the ic's datasheet and change or disable the protection
            Datasheets on these components is difficult to find. I cannot find anything on google for the inverter board. do you have suggestions on websites that do not have their databases indexed by google?

            Comment

            • R_J
              Badcaps Legend
              • Jun 2012
              • 9535
              • Canada

              #7
              Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

              What's the number on the ic? Is'nt it a TL494C?
              Last edited by R_J; 05-19-2020, 06:40 PM.

              Comment

              • dick_barton
                Badcaps Legend
                • Aug 2015
                • 6642
                • Wales

                #8
                Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

                Not really a good idea to remove protection other than to help serviceing. The TL494 is the driving IC.
                There is some information in the thread TV Repair Reference Library.
                Willing to help but I'm no expert.

                Comment

                • spartantravis
                  Member
                  • Nov 2019
                  • 17
                  • Italy

                  #9
                  Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

                  I think I may have fixed it without removing the Protection circuit. I identified the problem with the flickering. There was black charring all around the CCFL that was malfunctioning. I am guessing that the bulb was arcing due to degradation of the wire soldering. I resoldered it (with incredible difficulty) and reassemblied the tv. It functions for the time being so I dont need to remove any circuits. The thing is a fire hazard though so if you hear a story about a house burning down due to a Technika TV, ,you can say "I tried to tell you"

                  Comment

                  • nomoresonys
                    Badcaps Legend
                    • Jan 2013
                    • 12196
                    • U.S.

                    #10
                    Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

                    Well at least you weren't dumb enough to disable the protection, ccfl run way too hot for that noise.
                    Last edited by nomoresonys; 05-20-2020, 01:49 PM.

                    Comment

                    • nomoresonys
                      Badcaps Legend
                      • Jan 2013
                      • 12196
                      • U.S.

                      #11
                      Re: Technika X22/14C-GB-TCD UK - Flicking backlight: How to disable the Protection Li

                      By that I mean very high voltage compared to led backlighting.

                      Comment

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