Protek A434L Operating Manual page 86

 Calibration accessories (optional)
Calibration Kit which contains one 50ohm load, one Open

standard and one Short standard
 Test cable: Use a phase stable cable for reliable and consistent
measurement results
To minimize measurement errors, connect the port extension cable
to the RF In port on the instrument and then connect the Cal Kit to
the end of the extension cable.
The Figure 4.7 shows the connection diagram for calibration using a test
cable. To compensate measurement errors due to the test cable or adapters,
perform the Open-Short-Load (O-S-L) calibration including the test cable.
For detailed calibration procedure, refer to Table 4.2 Calibration Procedure
Figure 4.7 DTF Calibration Connection Diagram
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