Agilent Technologies PSA Series Service Manual page 192

Hardware Options
Overview and Verification of Option 123, Microwave and Millimeter Preselector Bypass
highband mixer. Steps will also appear at 13.2 GHz and 19.2 GHz.
5. Tune the source and PSA to 10 GHz, 15 GHz, and 20 GHz and check
the signal level. The accuracy of the measurement will depend on the
source flatness, the quality of the interconnect cable, and the
frequency response of the PSA.
6. See the foldout block diagram Option 123 (E4440A, 43A, 45A) for
signal level troubleshooting.
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