Samsung Power Supply Board BN44-00874F

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  • nomoresonys
    Badcaps Legend
    • Jan 2013
    • 12332
    • U.S.

    #81
    You don't see a resistor there because there isn't one.

    Comment

    • Nicktronic
      Badcaps Veteran
      • Mar 2023
      • 247
      • Canada

      #82
      All the SMD resistors test fine as far as I can tell.

      Comment

      • Davi.p
        Hobbist Tech
        • Sep 2009
        • 4544
        • Italy - Milan

        #83
        what you use to remove the insulating glue? primary side of the two transformers tested? CM801s , CM802s, DM807 Tested? what voltage on cathode of DM807?

        Comment

        • Nicktronic
          Badcaps Veteran
          • Mar 2023
          • 247
          • Canada

          #84
          Originally posted by Davi.p
          what you use to remove the insulating glue? primary side of the two transformers tested? CM801s , CM802s, DM807 Tested? what voltage on cathode of DM807?
          I used isopropyl, a brush and a plastic spudger. All components tested good. Cathode of DM807 on power up was 5.45VDC slowly discharging at a rate of 0.01vdc/second

          Comment

          • Davi.p
            Hobbist Tech
            • Sep 2009
            • 4544
            • Italy - Milan

            #85
            Search in secondary side for a TL431 or equivalent in sot23 and replace it, 5,5v is too low, before it check the main stage ic primary side with its datasheet, if vcc is as usual around 16v then is so..

            Comment

            • Nicktronic
              Badcaps Veteran
              • Mar 2023
              • 247
              • Canada

              #86
              Hi, I will get to this, just been really busy!

              Comment

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