I'm new to working with vector network analyzers (Rohde & Schwarz ZNB4) and would like to ensure that the measurements I'm making are accurate.
The project I'm working on has two phases. In the first, I'd like to measure the impedance of an unknown load. The connection is made directly to the VNA using a 6" length of RG-58 which has been "doctored" such that it terminates at the load using flying leads. The first question, then, is should I use this connector in the calibration by simply removing the load and making a reflected osm by opening, shorting, and terminating the leads with a 50-ohm discrete resistor? Would it be better to remove this connector and use a cal. kit directly off the port?
After calibration using the latter method, I took a measurement and found that the load is far less than 50 ohms at its design frequency (around 12 +j10 ohms). For this reason it was advised that I check into the offset de-embedding function of the VNA to reconfigure the port to simulate a matched line. Is this something that should be done?
In the second phase, the load will be driven by the VNA after adding a 50 dB amplifier and about 6 ft. of coax. Will I need to recalibrate?