Port extension compensation is done to compensate the phase shift when the port is extended by a cable connected from the calibration reference plane (generally 7-mm terminal of test head). This function regards the transmission line as a distributed parameter circuit without loss. Usually, port extension compensation is available only when Arbitrary is selected for fixture type.
Perform the port extension compensation as follows:
Press Cal > Port Extension and input the desired port extension value.
You can set the port extension value in either electrical length or delay time. When the port extension value is set by one of these keys, the value is converted to the other unit and displayed on the bottom line of the setting parameter area in small letters. You can also see the converted value in the setting parameter area by pressing the other key.
Press Extension > toggle between ON|OFF to turn ON/OFF the port extension compensation.