Cisco 7246 - uBR Router Hardware Installation Manual page 141

Chapter 4 Connecting the Cisco uBR7200 Series Router to the Cable Headend
Figure 4-50
Before moving on to
Note
source.
On your spectrum analyzer, narrow both the resolution and video bandwidth to 1 MHz. You will notice
Step 3
that the preamble of the signal has dropped in amplitude, yielding a spectrum analyzer display similar
to the one in
OL-5421-03
Vector Signal Analyzer Plot of Upstream Data Burst (Preamble Only)—Digital
Demodulation Mode
Step 3, be sure to hook your spectrum analyzer back up to the upstream signal
Figure 4-51.
Cisco uBR7200 Series Universal Broadband Router Hardware Installation Guide
Measuring the Upstream RF Signal
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