leakage and average in FFT - HELP PLEASE

[Eng P&D]

Please, someone can tell me why I'm taking diferent values of RMS averaging in this vi.
And about leakage around the main frequency, i try to use zoom fft but i don't get the result like the ones you have in tutorials, althougt using frequency resolution of 1 Hz the FFT gives leakage for this simple sinal.
I have read more than 5 articles about FFT on labview but I don't understand what the hell is going on.
I need to talk with someone to answer some doubts. Manager is doubting the credibility of labview fft measurements, but may the problem is the one in front of computer.
So bad day today.
If someone could help me, thanks.

[Eng P&D]

here is the vi.

[Eng P&D]

ok ok... sorry for the post, I have found the one problem, difference between power and fft spectrum, but there're always some question.
May someone sugest how can I make to test an analitical example and compare with labview results?
I believe in labview but problem is with manager.

[AESulzer]

I'm afraid that I don't quite understand your question. What do you mean by an "analytical example"? Are you simply looking for a way to compare LabVIEW's analysis algorithms with those of another environment? If so, I would recommend taking a simple example out of a textbook or from online and implementing it in both languages; however, it should be noted that no two languages will give you the exact same results, as exact results are completely dependent on the implementation of the code underlying the algorithm.

Also, I know you mentioned that you've read a few articles, but I wanted to make sure that you looked at this one because I think you may find it useful. It details the algortihms underlying the FFT and Power Spectrum functions in LabVIEW.

[Eng P&D]

Thanks for answer,

This one I've read too. But some of my problems were solutioned.
We simulate a square wave with signal generator and then make some analysis, and get good results.