I am trying to use the vi "FFT Spectrum (Mag-Phase) VI", and I made a sample program to test it out, but I have encountered a problem regarding the scaling that I am confused by. The LabVIEW program is attached. In this program I create two sine waveform generators of ampltude 1 and with two different frequencies (20 and 30 Hz), and I append them together before sending them into the FFT vi. My problem is that I don't understand the output in the amplitude spectrum graph. It shows two peaks situated at the right frequencies, but their amplitudes aren't what I was expecting. The amplitude of the peaks are about ~0.35, but I was expecting them to both be 1 since I was inputing two sine waves with amplitude 1. Obviously the scaling is wrong, but I don't understand why. How do I correct this? Also, lets say I append together 20 sinewaves instead of two as in the example shown or instead input some generated noise. How would I scale the resuts so that everything would result with the expected amplitudes I was expecting?
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