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Calibrating for Increased Measurement Accuracy
Calibrating for Noninsertable Devices
Adapter Removal Calibration (ES Analyzers Only)
Adapter removal calibration provides the most complete and accurate procedure for
measuring noninsertable devices.
The following adapters are needed:
Adapter A1, which mates with port 1 of the device, must be installed on test set port 1.
Adapter A2, which mates with port 2 of the device, must be installed on test set port 2.
Adapter A3 must match the connectors on the device under test (DUT).
NOTE Adapter A1 and Adapter A2 become part of the test setup to allow connection
to the DUT. Adapter A3 is used during calibration only. Its effects will be
removed.
Figure 6-13 Adapters Needed
Other requirements include:
Calibration standards for performing a 2-port error correction for each connector type.
Only recognized cal kit standards are ava ilable. SSMA, SMX, GPO and similar
connectors have no recognized traceable cal kit standards.
Specified electrical length of adapter A3 within ± 1/4 wavelength for the measurement
frequency range.
For each port, a separate 2-port error correction is performed,the first at the connection
between A1 and A3, and the second at the connection between A2 and A3. The error
coefficients are stored in separate calibration sets. After these calibrations, the two
calibration sets are combined and, with knowledge of the electrical length of the adapter
A3, a separate third calibration set is created. This cal set contains error coefficients that
accurately represent the characteristics of Port 1 and Port 2, as if A1 and A2 were actually
connected together to measure forward and reverse match and tracking terms.