Agilent Technologies FieldFox MW N9913A, Руководство по обслуживанию

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5-26 N9927-90003
Theory of Operation FieldFox Analyzer
User Calibration in CAT, NA, and VVM Modes
User Calibration in CAT, NA, and VVM Modes
There are three types of calibrations for the CAT, NA and VVM modes: CalReady, QuickCal and
Mechanical Cal. See the
FieldFox Analyzer User's Guide (Part Number N9927-90001) "Calibration for
CAT, NA and VVM Modes" section for specific instructions for performing these calibrations. Because
NA, CAT, and VVM modes are very similar, a calibration that is performed in one mode can also be
applied in the other modes.
When a user calibration is performed, the full frequency range of the analyzer is calibrated even though
the current state of the analyzer may be less than the full range. This allows a calibration to be
"interpolated" beyond the frequencies set at the time of calibration (an asterisk "*" on the display
indicates interpolation).
Do not leave cal standards connected to the PORT 2 or PORT 1 ports for more than three minutes. Heat
in the port connectors may affect the accuracy of the standards.
Factory Calibration (CalReady)
When the analyzer is adjusted at the factory or during annual calibration, a preset calibration is stored in
the analyzer (CalReady).
The preset calibration covers the full frequency range of the analyzer. The preset calibration is active
whenever “CalRdy” is displayed on the left side of the screen. Presetting the analyzer activates the preset
calibration.
The preset calibration provides very good measurement performance at the PORT 1 and Port 2
connectors when the analyzer has thermally stabilized at room temperature.
The preset calibration should be re-characterized every 12 months to maintain accuracy. This is
accomplished via the Error Terms adjustment in the TME. Refer to
Chapter 3 .
QuickCal
The QuickCal function mathematically “extends” the preset calibration to the end of a cable or adapter. It
is a firmware only function; it does not involve analyzer hardware.
Table 5-1. Cal Status Indicators
Indicator Meaning Additional Indicators
CalRdy Preset (factory) calibration is active
* = interpolation active
? = Measurement conditions have changed.
Cal ON Q QuickCal calibration is active
* = interpolation active
? = Measurement conditions have changed.
Cal ON U User calibration is active
* = interpolation active
? = Measurement conditions have changed.
Cal OFF Calibration is inactive
Cal OFF*
No calibration available to activate for
this measurement.