|Spur cluster walk from 10.640MHz up in steps of a few kHz.|
|Spur cluster peak unrolling across Nyquist intervals|
Indeed, you can do the same thing at a lower sampling rate. This both shows the fine scale structure and the harmonic spurs and verifies the above unrolling at a different set of frequencies. The following is a 2.5MSPS capture of a 10.640MHz input signal.
|10.640MHz input signal using 2.5MSPS showing the spur cluster internal structure.|