Agilent Technologies FieldFox N9913A - Port Cable Trimming Measurements

VVM (Vector Voltmeter) Mode 145
How to select Zeroing
 Press Meas Setup 4
 Then Zero
 Press Zero OFF to turn zeroing off.
1-Port Cable Trimming Measurements
A 1-Port Cable Trimming measurement is used in a cable fabrication procedure
to validate proper electrical length.
FieldFox Block Diagram
 The R receiver measures incident signal (green
line) out of the source.
 The A receiver measures reflected signal (red line)
from the end of the DUT (black line).
 In VVM mode, the display ALWAYS shows ratioed
(A/R) measurements which is the electrical length of
the DUT.
How to make a 1-Port Cable Trimming Measurement
1. Press Mode then VVM then 1-Port Cable Trimming.
2. Press Freq/Dist then enter the frequency for the measurement.
3. To improve measurement stability, change the IF Bandwidth, Output Power,
and Averaging settings as needed.
4. Press Meas Setup 4 then Zero OFF.
5. Optionally calibrate the FieldFox. Learn more about VVM calibration on page
144.
6. To ensure that the calibration is adequate, perform the following optional
Measurement Verification procedure.
NOTE This measurement verification procedure is suitable for low frequency
measurements. However, for high frequency measurements, a more sophisticated
procedure is required.
a. Connect a short standard to PORT 1 where cables to be trimmed
will be connected.
b. Press Meas Setup 4 and press Zero.
c. Remove the short standard and connect the open standard.
d. Confirm that magnitude measurement is less than –0.1 dB and that
the phase value reads 180° degrees.
7. Attach the shortest cable to the FieldFox PORT 1 connector. This cable is the
reference cable. Leave the end of the reference cable open (unterminated).
8. Press Meas Setup 4 then press Zero.
9. Remove the reference cable from the FieldFox PORT 1 connector.