On Sat, Jan 4, 2020 at 10:11 PM, Gary O'Neil wrote:
Three port terminations are identified as sufficient to represent a short
circuit (zero ohms), and open circuit (infinity ohms), and a load standard (Z0
+/-j0 ohms). These devices are measured and plotted on the display at the
locations representing the reflection coefficient values they are intended to
represent (-1 +/-j0, 0 +/-j0, and 1 +/-j0
Gary,
The point Jef wants to make is that above statement is NOT true for well characterized but non perfect calibration standards. The characterization (polynome) will describe where for instance the "open" should be seen on the smith chart. The same is true for the load. Adding a first characterization in the form of a small constant C makes the load move away from 0+j0 at higher frequencies. So the characterization of the calibration standard is not there to fix them at -1 +/-j0, 0 +/-j0, and 1 +/-j0 but to have the actual impedance reflected
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