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Measuring diff impedance with 4396b and S param set

Question asked by newguy on Oct 18, 2007
I am trying to take a differential impedance measurement on a 10' length of cable using a 4396B and 85046A S param set.  I am using a 50 ohm coax off the port one to a 50:100 BALUN.  The wires of the twisted pair being tested are connected to ports A and B of the BALUN.

I have completed the S11 port calibration (open/short/load) using a 100 ohm resister across ports A and B of the BALUN.

I am viewing the results in the Smith chart format with my marker set at 1 MHz.  The 4396B is giving me three measurements at my marker.  The first two are in ohms and the third is capacitance. 

I am not sure how to verify I am getting accurate results.  I don't have a sample of known values to test.  The impedance of this cable was measured on a LF Impedance analyzer and found to be 106 ohms.  Can I use this to verify my differential measurement results?

Thanks for helping a newbie!  

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