Learn how to make 75Ω measurements at the FieldFox Supplemental User‟s
Guide:
How to set System Impedance
Press Meas Setup 4.
Then
Then scroll to System zo and press Edit.
Then type either 50 or 75 and press Enter.
Port Extensions
Port extensions allow you to electrically move the calibration reference plane on
either port 1 or port 2 after you have performed a calibration.
Why use Port Extensions
Use port extensions if you are unable to perform a calibration directly at your
device because the location is not accessible. Perform a calibration at a
convenient place, then use port extensions to compensate for the time delay
(phase shift) to the desired reference plane. On the FieldFox, port extensions
does not compensate for the loss of the additional electrical length, nor any
mismatch errors beyond the calibration reference plane.
Also use port extensions if you have already performed a calibration, and then
decide that you need to add a length of transmission line in the measurement
configuration. Use port extensions to "tell" the FieldFox that you have added the
length to a specific port..
With S11 and S22 reflection measurements, the FieldFox doubles the port
With S21 and S12 transmission measurements, the port 1 and port 2
Port extensions and Electrical Delay differ in the following ways:
Electrical delay applies to a specific trace
Port extensions apply to specific hardware ports
Port Extensions and Electrical Delay can be set independently. When both are
set, the delay adds together. Learn more about Electrical Delay on page 25.
How to apply Port Extensions
Press Meas Setup 4.
Then
Then
Then
Then enter time value using the numeric keypad, the ▲|▼ arrows, or the
30
http://na.tm.agilent.com/fieldfox/help/
Settings
extension valued that you enter to account for the additional delay in the
forward and reverse directions.
extensions are added together. This accounts for the total transmission delay
going through ports 1 and 2.
Port Extensions
Port Extensions ON
Port1 Extension
rotary knob. Press
Enter
or
Port2 Extension
or select a seconds (time) multiplier.
N9923A FieldFox User's Guide