why the time of maximum does not change if use FFT Spectrum (Mag-Phase).vi

[hafizzuddin]

hi all

i'm just testing a simple program to detect time of the maximum peak of an FFT graph. the problem is when i use FFT Spectrum (Mag-Phase).vi, i can't get the value for its maximum time. But if i used Spectrum Measurement express vi, it can give me the value. How can i get the value using FFT Spectrum (Mag-Phase).vi ?

[ceties · Accepted solution]

It's not clear what you are asking. You say that you try 'to detect time of the maximum peak of an FFT graph' which is nonsence unless you would apply STFT or some other transform of this type. FFT gives you frequencies vs magnitudes!!!! Not time. So it appears to me that you try to get the frequency of the harmonics with maximum magnitude, right? If so see attached snipet.

Message Edited by ceties on 04-07-2010 10:12 AM

[hafizzuddin]

thank you..this answers my question...