Toshiba sdp7000 no sound

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  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #21
    Re: Toshiba sdp7000 no sound

    That is not good, I cannot see that both or one of pin 4 on the IC has internal short, but that is the possibility.
    5V feeding the series connected resistors 4700 ohms and 1900 Ohms to ground, it will never get to 2V at the junction of the two resistor.
    Last edited by budm; 11-09-2012, 01:18 AM.
    Never stop learning
    Basic LCD TV and Monitor troubleshooting guides.
    http://www.badcaps.net/forum/showthr...956#post305956

    Voltage Regulator (LDO) testing:
    http://www.badcaps.net/forum/showthr...999#post300999

    Inverter testing using old CFL:
    http://www.badcaps.net/forum/showthr...er+testing+cfl

    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
    http://s807.photobucket.com/user/budm/library/

    TV Factory reset codes listing:
    http://www.badcaps.net/forum/showthread.php?t=24809

    Comment

    • efilnikufecin
      Member
      • Nov 2012
      • 13
      • USA

      #22
      Re: Toshiba sdp7000 no sound

      Originally posted by budm
      That is not good, I cannot see that both or one of pin 4 on the IC has internal short, but that is the possibility.
      5V feeding the series connected resistors 4700 ohms and 1900 Ohms to ground, it will never get to 2V at the junction of the two resistor.
      After reading that post, I figure you have decided the amp chips are fried. That would pretty much write it off in my mind so I decided to try something on my own. once we eliminated c118\115 from the circuit, that left ic100/101 and r127 being the possible paths to ground. I removed r127 raising the resistance to over 100K to ground. When I re-applied power still no sound, but now I got 4.99 volts at pin 4 of ic100/101.

      It's 2AM here, I'm going to bed, and maybe think about it more tomorrow. I'm starting to think the amp chips are just blown at this point though. I doubt I could solder new ones in, but I think I can still get line level output to the headphone jack for my sons video games.

      Comment

      • budm
        Badcaps Legend
        • Feb 2010
        • 40746
        • USA

        #23
        Re: Toshiba sdp7000 no sound

        It sure sounds like it since ypu have all the required voltages. I know they are Class D but still, no heat sinks and they expect it to last.
        Never stop learning
        Basic LCD TV and Monitor troubleshooting guides.
        http://www.badcaps.net/forum/showthr...956#post305956

        Voltage Regulator (LDO) testing:
        http://www.badcaps.net/forum/showthr...999#post300999

        Inverter testing using old CFL:
        http://www.badcaps.net/forum/showthr...er+testing+cfl

        Tear down pictures : Hit the ">" Show Albums and stories" on the left side
        http://s807.photobucket.com/user/budm/library/

        TV Factory reset codes listing:
        http://www.badcaps.net/forum/showthread.php?t=24809

        Comment

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