I'm configuring my LMX2594EVM eval board to generate various integer-mode clocks. I'm using a 100MHz reference and my configuration and outputs are shown below.
I'm curious about the large spur at 2.38GHz with the 4.8GHz output and at 2.58GHz, 1.28GHz and 120MHz with the 5GHz output. Are these really coming out of the LMX, or could they be some sort of measurement error/artifact? The device is operating in integer mode and those large spurs don't seem to be obviously related in frequency to the fundamental.
I'm using a Tek RSA-306B to measure this - the last plot shows the spurs that are from the instrument itself (LMX is powered down).
Thanks
3GHz:
4GHz:
4.8GHz:
5GHz:
5.6GHz:
LMX output powered down:
