HP 8712ES User Manual page 75

Port 1: Open, Short, Load Connections
NOTE
5. Press Measure Standard
6. Next, the instrument prompts you to connect three standards (open,
short, and load) to port 2. Instead of connecting the standards directly
to port 2, connect them to the open end of the cable. This end of the
cable will become the calibrated port 2 for measurements. See the
graphic above.
7. The analyzer will measure each standard and then calculate new
calibration coefficients. The message "Calibration complete."
will appear for a few seconds when the analyzer is done calculating
the new error correction array.
Changing sweep frequencies (and other source parameters) may affect
your calibration. See
ES User's Guide
Measuring S-Parameters using a Two-Port Calibration
Port 2: Open, Short, Load Connections
after connecting each standard.
Chapter 6 for more information.
Making Measurements
3-23