FFT vi truncate the FREQ of signal.

Hello

I noticed that the FFT vi truncate my signal. See attachments.

I'm basically the noise of a signal (I have both the phase - I - and out of phase - Q-signals...)

(Ignore the vi curve, it is just to remove the continuous component of the signal, it's irrelevant to this discussion).

Kind regards

Ali

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You lose your calendar information for data going to the graph of the PSD.  It works on arrays.  The FFT functions assume a dT or dF 1.  So when things are placed in the chart, you will see values up to 0.5 since Nyquist limits you to 1/2 of the sampling frequency.  PSD2 graph doesn't have this problem because the blue wire of the DDT keeps the calendar data.

If you build your table in a type of waveform data and the boot in the value of dT, your data should look like the other graph.

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