Campbell Scientific RTDAQ Software - Manual (Page 146)

Section 6. View Pro
6.7.5 FFT
From the FFT screen, you can view FFT data. The FFT button on the toolbar
will be enabled if there is at least one valid FFT in the currently selected data
file.
View Pro does not create FFT data from time series information.
It only displays FFT data contained in a *.DAT file. FFT data in
the *.DAT file is created by using the CRBasic FFT instruction
in a CRBasic program Data Table. NOTE
View Pro cannot display FFTs from a TOACI1 data file. NOTE
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