Effect of oscilloscope AC coupling when measuring very low frequencies

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  • japlytic
    Badcaps Legend
    • Oct 2005
    • 2086
    • Australia
    #1

    Effect of oscilloscope AC coupling when measuring very low frequencies

    When applying a square wave of a very low frequency (5 Hz) from a signal generator to an oscilloscope, the waveform looked distorted. I thought it was a fault in the signal generator.
    Later, I found out when I used DC coupling, the waveform had no distortion.
    DC coupling should be used when the application permits.

    Additional information can be found at:
    http://www.tek.com/Measurement/cgi-b...=oscilloscopes
    http://zone.ni.com/devzone/cda/ph/p/id/9
    Attached Files
    My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.
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