On 7/1/21 6:41 AM, Zack Widup wrote:
I wouldn't sweat all these matching transformers, etc.? 75 isn't far from 50, so you're not going to have a "math and measurement" precision issue.
What I would do is get your 75 ohm cable, Calibrate using 50 ohm load, short, and open at the *end* of the cable and the fact that it's a 75 ohm cable is absorbed into the calibration.
Then, if you want to know VSWR or S11 for a 75 ohm system, convert your 50 ohm data to a 75 ohm reference impedance using math.
OR - get a 75 ohm termination, do the cal using 75, short and open, and your data will all be with reference to a 75 ohm system.? S11 and VSWR will be correct. What might not be correct is the resistance in the .s1p file and the reference impedance at the center of the Smith chart.
