I have some microstrip traces that were designed to be 50 ohms, but I'd like to find out what they really are. I have a network analyzer good to 6GHz at my disposal. Does anyone have a favorite means of doing this? This was my thought:

-- Terminate the trace in 50 ohm loads

-- Have the network analyzer plot S11 up to whatever frequency corresponds to at least half a wavelength; this will ideally display a circle that has one edge at the center of the Smith chart (Zin=50 ohms) and the other edge either greater than Z=50 if Z0 of the microstrip is >50 ohms or less than Z=50 if Z0 of the microstrip is