FFT plot on data sample

[Joven]

Dear all,

I have attached a txt file collected from a sensor. The sampling rate is 25600 samples per second and the number of samples is 20000 samples. May i know how do i properly plot out the FFT to view the dominant frequency of this plot?

Thank you!

[GerdW · Accepted solution]

Hi Joven,

use a FFT function to find our frequency peaks:

(Peak at ~602Hz?)

[Joven]

Dear sir,

Yah i also similar method to plot this. I have attached this new text file which is the correct one.  Is there any indication that the dominant frequency is at around 40 to 50 Hz?

How can i push this to be plotted to see the time-freq response?

[Henrik_Volkers]

602.17 Hz if a tone detection is applied 😉

for the second the first dominant frequency is

12,47 followed by 25,3

[Joven]

Yah i also similar method to plot this. I have attached this new text file which is the correct one.  Is there any indication that the dominant frequency is at around 40 to 50 Hz?

How can i push this to be plotted to see the time-freq response on a spectrogram?

[Henrik_Volkers · Accepted solution]

here  is my code... Q&D

feed the wfrm into the spectrogram vi ...

the resolution of your samples is not very high 😉

[Joven]

Dear sir,

You are finding the highest amplitude with its freq in time domain directly? The amp and freq vi will automatically find the dominant frequency? What does the residual setting in this vi does?

Will fft in the frequency domain provides a better interpretation? I am figuring out whether i can find anything between 40 to 50 Hz dominant frequency as i am simulating it with a source that provides this range.

Thank you!

[Henrik_Volkers]

That's is a quick and dirty written vi.

For details hoover over the subvis, rigth-click and read the help 😉