Midi controller power issue

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  • johnnydiaz
    Senior Member
    • Apr 2012
    • 52
    • USA

    #1

    Midi controller power issue

    My midi controller which is powered via usb is not powering up. So I opened it up and remove the power board and checked the voltages. On the usb input I get 5 volts and on the V+BUS5D output connection cable to the next board I get 5 volts. So far so good. Now when I connect the power board to the next board the voltage drops to 4 volts on the main power board and also on the second board. I disconnect the second board and now I have 5 volts on the power board by itself. What could be the casue of this symptom?
  • cadiman
    Badcaps Veteran
    • Mar 2010
    • 397

    #2
    Re: Midi controller power issue

    5 volts means nothing with no load.

    What are you plugging your usb into?

    Comment

    • budm
      Badcaps Legend
      • Feb 2010
      • 40746
      • USA

      #3
      Re: Midi controller power issue

      Any pictures of the boards?
      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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