Hisense 50k680 no power no standby

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  • dick_barton
    Badcaps Legend
    • Aug 2015
    • 6643
    • Wales
    #21
    Re: Hisense 50k680 no power no standby

    Thinking again about this problem.

    Initially there was 15V at Pin 6 (VCC) of N851. This voltage comes from VDD via transistor V902. There is a 16V zener (VZ901) at the base of this transistor so the emitter would be at approximately 15.3V.

    However the +20V supply for V902 comes via T901-VD905 and smoothed by C908.

    This must mean that N842 must be working (PFC) in order to drive the transformer T901 to derive the +20V from one of its windings.

    So you should have 12V at the output connector XP805. Do you?

    Can you check the DC voltage across the two legs of C822 to see what the PFC voltage is.
    Willing to help but I'm no expert.

      Comment

      • EUWest
        Member
        • May 2019
        • 44
        • Germany
        #22
        Re: Hisense 50k680 no power no standby

        Hey dick_barton! Thanks for your reply. I think i killed the Board while replacing R906. Think Used to much heat and than Board wäre inflated at this Area.

        Saw on Aliexpress Replacement Boards, im willing to order one and hope its solve the Problem.

          Comment

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