Keysight Technologies 85054B, Руководство пользователя и сервисное руководство

Страница: 26 / 65

3- 6 85054B
Use, Maintenance, and Care of the Devices
Gaging Connectors
Gaging Connectors
The gages available from Keysight 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.