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Looking for a waveform function....

Hello,

     I am starting to use more waveform type functions, and I am looking for some thoughts as to how to go about doing it. There might already be waveform functions to already do what I am looking for, so I thought I would ask.

      So I will have a waveform to start with from a measurement from a DMM in voltage digitizer mode. It will have recorded an AC voltage waveform for a certain period of time. The frequency and amplitude should be fairly constant for most of the waveform, and then at some point in the measurement, the signal stops (or drops below a certain threshold). So I am trying to measure the time from the first point in the waveform, to when the signal drops. I did some asking around, and some have said I am looking for a "signal window" function? Obviously on a scope, this is easy to see and measure. Which waveform functions might I be able to use? Thanks....

 

waveform.gif

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Hi z4,

 

you might calculate the first derivative from your signal.

When the derivative stays below a certain threshold for more than x samples the signal is "stopped"…

Best regards,
GerdW
CLAD expired, using 2009SP1 + LV2011SP1 + LV2017 (+LV2018 sometimes) on Win7+cRIO
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