Agilent Technologies N5242A, Руководство по обслуживанию

Страница: 65 / 342

Service Guide N5242-90001 3-33
PNA Series Microwave Network Analyzers Tests and Adjustments
N5242A Performance Tests
Calibration Coefficients Test
Function of the Test: To verify the uncorrected calibration coefficients of your analyzer.
The calibration coefficients are measured in forward and reverse direction. Refer to
Appendix 8, “General Purpose Maintenance Procedures” for error term information
relating to the calibration coefficients measured.
Specification Tested: Uncorrected System Performance
Equipment Used: A calibration kit and a test cable.
Description of the Test:
1. A series of 2-port calibrations are performed. Two full SOLT 2-port calibrations are
performed on each port. Isolation is turned off during each 2-port calibration.
2. A test cable is attached to the first port, and a calibration is performed at the end of the
cable and at the second port. The cable is moved to the second port and another
calibration is performed. Using two calibrations helps to eliminate the unknown
characteristics of the through cable.
3. Each calibration produces 12 error terms.
4. The error terms are used to determine the following characteristics: directivity, source
match, load match, reflection tracking, and transmission tracking.
If the Analyzer Fails this Test:
• If the analyzer fails tracking error terms only, perform “Receiver Adjustment” on
page 3-39 and repeat this test.
• Failure of any other error terms indicate a hardware failure. Refer to the appropriate
error term discussion in Chapter 8, “General Purpose Maintenance Procedures,’ for a
typical cause of failure. Refer to Chapter 7, “Repair and Replacement Procedures,’ for
instructions on replacing the suspected faulty component or assembly.