HP HP 8712ET, User Manual, Page: 256 / 480

6-30 ET User’s Guide
Calibrating for Increased Measurement Accuracy
Checking the Calibration
To perform a calibration check:
1. Be sure that the analyzer is in the measurement mode and has
implemented the particular calibration that you want to check.
2. Press .
3. Follow the onscreen prompts to connect the calibration standards.
(You should connect the standards at your calibration reference
plane, not necessarily at the front panel of the analyzer. For example,
your calibration reference plane may be at the end of cables, adapters,
or test fixtures connected to the analyzer. See
“The Calibration
Reference Plane” on page 6-5 for more information.)
CAUTION
To decrease the likelihood that a faulty calibration standard is being
used, it is recommended that you use a different set of calibration
standards for the calibration check than you used to perform the initial
calibration. The different set of calibration standards must be of the
same type as the original set.
4. Once you have properly connected all the required standards as
prompted, the analyzer computes the residual errors for the
measurement.
5. Now press the key to view the residual errors for
the type of calibration you did a calibration check on. When you view
an error term plot, the analyzer stops sweeping and displays the plot
on the analyzer's screen. To return to measurement mode and
autoscale the display, press
.
6. Refer to “Error Term Descriptions and Typical Values” on page 6-31
for descriptions and typical plots of the various error terms.
CAL
Cal Check Do Cal Check
View Cal Check
Restore Meas