Odd result when doing simple sine excitation.
See attached XML file and screenshot.
Not that the excitation amplitude is 1, but the time-domain graph magnitude is very small. The dominant frequency is 2 Hz as requested, but many other frequencies are also included. Changing the amplitude to 10 increases the resulting magnitude and setting amplitude to 0 gets a 0 result.
This has something to do with seeting the stop and start frequencies in fourier tools. In this case, they were set from 100 to 200 (or 300?).