Cisco UBR7225VXR, Руководство по установке оборудования

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4-16
Cisco uBR7225VXR Universal Broadband Router Hardware Installation Guide
OL-17309-01
Chapter 4 Connecting the Cisco uBR7225VXR Router to the Cable Headend
Measuring the Downstream RF Signal
Figure 4-19 Measuring the RF Signal at the Upconverter Output in CATV Mode—Digital Channel
Power Screen
Step 9 Using the spectrum analyzer’s reference level control, adjust the amplitude of the displayed signal until
the signal peak is within the top graticule of the analyzer’s display grid, as shown in
Figure 4-20 .
Figure 4-20 Measuring the RF Signal at the Upconverter Output in CATV Mode—Adjusted Digital
Channel Power Screen
Step 10
Select the video averaging feature. Your spectrum analyzer should display a signal similar to the one
shown in
Figure 4-21 .