LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

fft of continuous sampled signal without toolkit

Im trying to take an fft of accelerometer data coming in from the daq. I was looking through the examples and found a lot of stuff that needed an FPGA target or the sounds and vibration toolkit. Can I get a proper fft without the toolkit?

 

When I look at the examples I can get a waveform that I expect but just using the fft function from the transforms pallette just seems to give me noise mostly.

0 Kudos
Message 1 of 5
(3,547 Views)

ok, so ive done some more searching and playing, I did find some examples using the power spectrum vi from the waveform measurement palette and the general shape of the waveform im getting seems correct but its not displaying the proper x axis. the waveform coming out of the power spectrum vi jumps around in really low frequencies like sub 1k. if I use the example FFT Analyses (DAQmx) the reading displays at the frequency I expect it to, so my physical setup has to be acceptable.

 

I posted a screen shot of what I have, is it possible to get this to display the correct frequency? or will I need the toolkit?

 

0 Kudos
Message 2 of 5
(3,533 Views)

Hi,

 

Any chance you could post the resulting waveform you received with an incorrect x axis?

 

Regards,

 

Finch Train

Message 3 of 5
(3,493 Views)

I figured out that I was being really stupid and had the samples per second low so that was limiting the range I had on the x axis. Thanks for the help though!

0 Kudos
Message 4 of 5
(3,462 Views)

Hi,

 

No worries! Small things like that can be the trickiest things to troubleshoot! Glad it worked out.

 

Regards,

Finch Train

 

0 Kudos
Message 5 of 5
(3,457 Views)