39.Displayed Average Noise Level, HP 8591EM

39.Displayed Average Noise Level,

HP 8591EM

This performance veri￿cation test must be performed with the EMC analyzer set in the spectrum analyzer mode.

This performance veri￿cation test measures the displayed average noise level within the frequency range speci￿ed. The EMC analyzer input is terminated in

50￿.

The LO feedthrough is used as a frequency reference for these measurements. The test tunes the EMC analyzer frequency across the band, uses the marker to locate the frequency with the highest response, and then reads the average noise in zero span.

To reduce measurement uncertainty due to input attenuator switching and resolution bandwidth switching, a reference level o￿set is added. The CAL OUT signal is used as the amplitude reference for determining the amount of o￿set required. The o￿set is removed at the end of the test by pressing instrument preset.

Equipment Required

Termination, 50 ￿

Cable, BNC, 23 cm (9 in)

Adapter, Type N (m) to BNC (f)

Figure 2-61. Displayed Average Noise Level Test Setup, HP 8591EM

Performance Veri￿cation Tests 2-265