Keysight Technologies FieldFox A Series, User Manual

Page: 127 / 756

Keysight N9927-90001 User’s Guide 127
Calibration for NA, CAT, and VVM Modes
— When your DUT has high return loss such as the reject band of a
filter. Then measuring the load improves accuracy. Even with the
optional Load, phase accuracy begins to degrade when the return
loss is greater than about 20dB.
— Press Skip Step in all other cases and when making DTF measurements.
Measuring a load would do little to improve accuracy.
Connect THRU (Not used for 1-port cals)
— Connect port 1 to port 2, either by mating the connectors that attach to the
DUT (Flush THRU), or by using a short jumper cable. Learn more about
Flush THRU in “Calibration Type” on page 134 . Then press Measure .
— Press Finish .
CAL ON Q is shown on the screen for all displayed measurements that are
corrected with QuickCal.
Using QuickCal with a Long Jumper Cable
QuickCal requires a sufficient frequency span to adequately characterize the
jumper cable (the cable between the instrument port and the DUT). If a ‘Cal
Failed’ error appears and you connected the optional Load standard, then
increase the frequency span of the measurement until the error no longer
appears. After the calibration, you can then decrease the frequency span as
needed and rely on interpolation. Learn more about Interpolation in
“Interpolation *” on page 140 .
QuickCal is also limited in how much jumper cable loss it can tolerate. If
QuickCal without the Load is failing, then measure the Load during the
QuickCal to see if that resolves the issue.
Mechanical Cal
Mechanical Calibration is performed using discrete standards from a Cal Kit.
Several Cal Kit definitions are built into the FieldFox. To learn about Cal Kit
definitions, refer to the Application Note, “Specifying Calibration Standards
and Kits for Keysight Vector Network Analyzers,” available online at
http://literature.cdn.keysight.com/litweb/pdf/5989-4840EN.pdf
Mechanical Cals are extremely accurate when performed using the correct Cal
Kits with standards that are clean and in good repair, and when using correct
connection procedures.
How to perform a Mechanical Cal
— Disconnect the DUT from the FieldFox.
Visit www.keysight.com/find/fieldfoxsupport to see a complete list of
supported Cal Kits. Also at this website, download Data-Link software that
allows you to edit Cal Kit definitions or add a new Cal Kit.