Keysight Technologies N8480 Series, Operating And Service Manual

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3 Service
48 N8480 Series Power Sensors Operating and Service Guide
Performance Test
Standing Wave Ratio (SWR) and Reflection Coefficient (Rho)
Performance Test
This section does not establish preset SWR test procedures since there are
several test methods and different equipment available for testing the SWR
or reflection coefficient. Therefore, the actual accuracy of the test
equipment must be accounted for when measuring against instrument
specifications to determine a pass or fail condition. The test system used
must not exceed the system Rho uncertainties shown in
Table 3- 1 when
testing the N8480 Series power sensors.
To check the calibration factor, the power sensor should be compared with
another recently calibrated power sensor. The source should be leveled
with a reference coupler that has low SWR and high directivity to monitor
or level the incident power.
For calibration factor and error analysis, refer to Keysight Application
Note AN1449- 1 to AN1449- 4 (Part 1 to Part 4), “Fundamentals of RF and
Microwave Power Measurement”.
N O T E
Waveguide power sensors only (N8486AR and N8486AQ)
• While the flange of the N8486AR is similar to the one described in MIL F-3922/54C-003,
the N8486AQ is modified to mate with the greater precision of MIL-3922/67B-006
flanges. The true position of the holes relative to each other are held to a diameter
tolerance of 0.0254 mm (0.001 in). The holes are held to 1.664 mm (0.0655 in) minimum
diameter while the pins are held to 1.61 mm (0.0634 in) maximum diameter.