08-22-2025 09:09 AM
Hey GerdW,
I have attached VI for V2019. I think it has something to do with axes. For 1kHz it gives 0Hz but for 1MHz peak is close to 0.1.
08-22-2025 09:24 AM
Hey Doug Thanks for the info,
Take a look at these, FFTs of 1KHz and 1MHz signals. X-Axis is looks messed up.
08-22-2025 09:47 AM - edited 08-22-2025 09:51 AM
You can fix the x-axis of the FFT graph by setting the dt of the waveform from the x-increment of the cluster here:
From your screenshots (and this won't change even after fixing waveform dt ==> FFT df):
The peak for the 1 MHz signal is in the 1M * 4m + 1 = 4001 bin
The peak for the 1 kHz signal is in the 1k * 4m + 1 = 5 bin
You can zoom in on the 1 kHz FFT graph to verify that the peak is not at zero.