Agilent Technologies 8510-58 manual Appendix B Dimensional considerations in coaxial connectors

Appendix B

Dimensional considerations in coaxial connectors

This appendix describes dimensional considera- tions and required conventions used in determin- ing the physical offset length of calibration standards in sexed coaxial connector families.

Precise measurement of the physical offset length is required to determine the OFFSET DELAY of a given calibration standard. The physical offset length of one and two port standards is as follows.

One port standard–Distance between “calibration plane” and terminating impedance.

Two port standard–Distance between the Port 1 and Port 2 “calibration planes.”

The definition (location) of the “calibration plane” in a calibration standard is dependent on the geometry and sex of the connector type. The “cali- bration plane” is defined as a plane which is per- pendicular to the axis of the conductor coincident with the outer conductor mating surface. This mat- ing surface is located at the contact points of the outer conductors of the test port and the calibra- tion standard.

To illustrate this, consider the following connector type interfaces:

7-mm coaxial connector interface

The “calibration plane” is located coincident to both the inner and outer conductor mating sur- faces as shown. Unique to this connector type is the fact that the inner and outer conductor mating surfaces are located coincident as well as having hermaphroditic (sexless) connectors. In all other coaxial connector families this is not the case.

3.5-mm coaxial connector interface

The location of the “calibration plane” in 3.5-mm standards, both sexes, is located at the outer con- ductor mating surface as shown.

Type-N coaxial connector interface

The location of the “calibration plane” in Type-N standards is the outer conductor mating surfaces as shown below.

Note

During measurement calibration using the Agilent 85054 Type-N Calibration Kit, standard labels for the “opens” and “shorts” indicate both the stan- dard type and the sex of the calibration test port. The sex (M or F) indicates the sex of the test port, NOT the sex of the standard. The calibration plane in other coaxial types should be defined at one of the conductor interfaces to provide an easily veri- fied reference for physical length measurements.

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