I have a doubt and I would appreciate if you could help me solving it please. I am using the VNA E5071C with a Picoprobe calibration substrate CS-5. What I would like to know is what Offset Z0 and what Arb. impedance exactly represent and the relationship between these two parameters and the System Z0. I would like to know this because in the VNA reference manual it says that "System Z0 should be changed to 1 ohm before calibration when using waveguide calibration kit and measuring waveguide devices" so I would like to know if it is necessary to do this with the CS-5.
I would also like to know something else. I am using GSG probes with a connection cable to the VNA. This cable has an impedance of aproximately 1 ohm. Is this impedance rigth? Shoudln't it be 50 ohm? By the way the DUT (device under test) I want to measure has a 50 ohm impedance.
Thank you for your help.