Agilent Technologies 85054D, Руководство пользователя и сервисное руководство

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3-6 85054D
Use, Maintenance, and Care of the Devices
Gaging Connectors
Gaging Connectors
The gages available from Agilent Technologies are intended for preventive maintenance
and troubleshooting purposes only. (See
Table 6-1 on page 6-2 for part number
information.) They are effective in detecting excessive center conductor protrusion or
recession, and conductor damage on DUTs, test accessories, and the calibration kit devices.
Do not use the gages for precise pin depth measurements.
Connector Gage Accuracy
The connector gages are only capable of performing coarse measurements. They do not
provide the degree of accuracy necessary to precisely measure the pin depth of the kit
devices. This is partially due to the repeatability uncertainties that are associated with the
measurement. Only the factory—through special gaging processes and electrical testing—
can accurately verify the mechanical characteristics of the devices.
With proper technique, however, the gages are useful in detecting gross pin depth errors on
device connectors. To achieve maximum accuracy, random errors must be reduced by
taking the average of at least three measurements having different gage orientations on
the connector. Even the resultant average can be in error by as much as
±
0.0001 inch due
to systematic (biasing) errors usually resulting from worn gages and gage masters. The
information in
Table 2-2 on page 2-4 assumes new gages and gage masters. Therefore,
these systematic errors were not included in the uncertainty analysis. As the gages
undergo more use, the systematic errors can become more significant in the accuracy of the
measurement.
The measurement uncertainties (see Table 2-2 on page 2-4 ) are primarily a function of the
assembly materials and design, and the unique interaction each device type has with the
gage. Therefore, these uncertainties can vary among the different devices. For example,
note the difference between the uncertainties of the opens and shorts in
Table 2-2 .
The observed pin depth limits in Table 2-2 add these uncertainties to the typical factory
pin depth values to provide practical limits that can be referenced when using the gages.
See
“Pin Depth” on page 2-3 . Refer to “Kit Contents” on page 1-2 for more information on
the design of the calibration devices in this kit.
NOTE When measuring pin depth, the measured value (resultant average of three
or more measurements) contains measurement uncertainty and is
not
necessarily the true value. Always compare the measured value with the
observed pin depth limits (which account for measurement uncertainties) in
Table 2-2 on page 2-4 to evaluate the condition of device connectors.