Just got an oscilloscope...

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  • Tom41
    Badcaps Veteran
    • Oct 2005
    • 336
    • England

    #1

    Just got an oscilloscope...

    And I was wondering if you lot have any tips or suggestions as to how I can use it to measure ripple current. I mainly want to use it to check the output of PSUs, both unloaded and under load, and see if the ripple is bad.

    I know that most PSUs do have a small amount of ripple, but how much is too much? So far I've measured a PC laptop PSU, and an Apple iBook PSU, both of which have some ripple. The PC laptop PSU seems to be a constant amount of ripple, but the iBook PSU has the ripple changing randomly! There also seems to be some interference creeping along the line on the scope when I measure that PSU - perhaps the PSU is going bad?
    You know there's something wrong when you open your PC and it has vented Rubycons...
  • bob8701
    New Member
    • Aug 2006
    • 1

    #2
    Re: Just got an oscilloscope...

    trigger by dc line, because ripple is related with ac frequency harmonic. by the way you need a load for power supply test.

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