# LabVIEW

cancel
Showing results for
Did you mean:

## Relative min and max of Waveform

I am wondering if I could get some help trying to capture a waveform measurement in LabView using an analog input.  I attached a picture of the waveform I'm trying to capture and the values I'm trying to read.  Would this type of measurement be possible in LabView

Message 1 of 4
(1,848 Views)

## Re: Relative min and max of Waveform

What rate is the waveform oscillating?  What rate do you plan to sample at?

As far as measuring those value, it is a matter of finding the right ranges to sample at.  What I have done for something somewhat simlar was to make a moving RMS on the entire waveform.  This should result in something like a square wave.  From there, you can look for the edges.  That will give you the ranges to do your amplitude calculations on the original waveform.

There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines
"Not that we are sufficient in ourselves to claim anything as coming from us, but our sufficiency is from God" - 2 Corinthians 3:5
Message 2 of 4
(1,836 Views)

## Re: Relative min and max of Waveform

The main frequency is approx. 20.5kHz and that frequency is modulated at approx. 17Hz.  I am currently sampling at 200k samples/sec

Message 3 of 4
(1,824 Views)

## Re: Relative min and max of Waveform

Alright.  A standard DAQ card should be able to do that.  If you aren't sure how to use a DAQ card and DAQmx, look in the LabVIEW examples.  Then try the analysis, which I described above.

There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines
"Not that we are sufficient in ourselves to claim anything as coming from us, but our sufficiency is from God" - 2 Corinthians 3:5
Message 4 of 4
(1,814 Views)