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FieldFox User’s Guide
If a jumper cable or adapter is required to connect the DUT to the FieldFox,
connect those components to the FieldFox test ports connectors. The effects of
those components will be measured and removed during the calibration, and
only the effects of the DUT will be displayed in the measurement results. These
should be high-quality components!
Do NOT connect anything at the cal reference plane where the DUT connects.
Press
Measure
Optionally Connect Load(s)
Connect a Load standard at the point where the DUT will be connected and
press
Measure
under the following conditions:
o
When a jumper cable has too much loss. If a ‘Cal Failed’ error appears and
you skipped the Load measurement, then perform the Cal again but
measuring the Load.
o
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 on page 73. 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 on page 77.
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.
NOTE
Visit
www.agilent.com/find/fieldfoxsupport
to see a complete list of supported
Cal Kits. Also at this website, download DataLink software that allows you to
edit Cal Kit definitions or add a new Cal Kit.