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Supplement for the User’s Guide (Firmware Version 7.68)
Calibration Considerations
Calibration Considerations
Clarifying Type-N Connector Sex
When you are performing error correction for a system that has type-N port connectors,
the softkey menus label the sex of the test port connector — not the calibration standard
connector. For example, the label, SHORT (F), refers to the short that will be connected to
the female test port. Since many devices have type-N (f) connectors, the calibration
standard to select is the type-N (m). Be sure to use the port extension pin on the type-N
(m) Open calibration standard.
NOTE Since the 85032F calibration kit offsets are equal for both male and female
connectors, the standard’s sex type is not requested during the calibration.
The Calibration Standards
During measurement calibration, the analyzer measures actual, well-defined standards
and mathematically compares the results with ideal "models" of those standards. The
differences are separated into error terms which are later removed during error correction.
Most of the differences are due to systematic errors—repeatable errors introduced by the
analyzer, test set, and cables—which are correctable.
The standard devices required for system calibration are available in compatible
calibration kits with different connector types. Each kit contains at least one short circuit,
one open circuit, and an impedance-matched load. In kits that require adapters for
interface to the test set ports, the adapters are phase-matched for calibration prior to
measurement of non-insertable and non-reversible devices. Other standard devices can be
used by specifying their characteristics in a user-defined kit, as described in the
“Modifying Calibration Kits” section of Chapter 7, “Operating Concepts.”
The accuracy improvement of the correction is limited by the quality of the standard
devices, and by the connection techniques used. For maximum accuracy, ensure that the
connectors are clean and use a torque wrench for final connections.
Electronic calibration (ECal) modules serve as the calibration standards for electronic
calibration procedures. ECal modules are electronic networks that simulate impedance
states that are similar to mechanical standards. The factory error correction for optimum
performance is embedded in the module’s memory.