Suitable resistor replacements?

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  • Agent24
    I see dead caps
    • Oct 2007
    • 4914
    • New Zealand

    #21
    Re: Suitable resistor replacements?

    I can't offer any concrete advice, only what I have heard and what I can remember (and which may be wrong)

    Might be worth waiting for someone else to answer as well, and\or reading up about it yourself: http://www.maxim-ic.com/app-notes/index.mvp/id/726

    If you already ordered it, might as well try it and see what happens. Pity you broke the original one though, especially if it turns out it wasn't faulty and you need it back...
    "Tantalum for the brave, Solid Aluminium for the wise, Wet Electrolytic for the adventurous"
    -David VanHorn

    Comment

    • daimoku
      Senior Member
      • Feb 2011
      • 85

      #22
      Re: Suitable resistor replacements?

      Thanks! I read as much about crystal oscillators as I could and I have to admit some of it is over my head at this point. However, it seems that orientation does not matter.

      Well, the Digikey order came in today. I installed the crystal by itself first to see if it exhibited the same symptoms and luckily it did (except no scratchy noise now)...whew!

      I knew the main board had a lot of bad caps so I replaced about 20 bad caps...mostly 35V470uF, a few 35V220uF. Now, the symptoms are slightly different.

      Before: The tv would run for a while and it would shut off on its own. After it cooled for 10-15 minutes, I could turn it back on.

      Now: The tv will run for a while and shut off on its own. However, I can turn it back on immediately.

      Mike - I took your advice and ordered extra of each common component to have them on hand for future repairs.

      I think I'm going to purchase/build an isolation transformer maybe with a built-in variac so that I feel more comfortable taking voltage measurements on a live circuit. That will make the troubleshooting process easier to hone in on which board to test.

      I hear a zapping noise coming from one of the power supply inductive components so I suspect it might have a short. I thought I checked it before, but I'll double check with the ring tester while it's cool and when it's warm.

      Any advice on the purchase vs build isolation transformers with or without built-in variac? Which transformers are well-suited for this task?

      Comment

      • Agent24
        I see dead caps
        • Oct 2007
        • 4914
        • New Zealand

        #23
        Re: Suitable resistor replacements?

        I'd re-post with details of your current work and findings in the TV section of the forum, in general electronics with a title about resistors I doubt it will get much attention.
        "Tantalum for the brave, Solid Aluminium for the wise, Wet Electrolytic for the adventurous"
        -David VanHorn

        Comment

        • belamex
          Member
          • Jun 2012
          • 12
          • USA

          #24
          Re: Suitable resistor replacements?

          DId anyone find a solution? My NS-LCD32 shut off suddenly. When I press the power button, only the green light comes on. no sound. no pic. I cannot figure it out. I want to test the PS but not sure what to test. Any pointers?

          Comment

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