Installation guide

5-45
Cisco uBR7100 Series Universal Broadband Router Software Configuration Guide
OL-2238-03
Chapter 5 Troubleshooting the System
Setting Downstream Test Signals
Configuring Unmodulated Test Signals
Configuring PRBS Test Signals
Verifying Test Signal Output
To verify the output of a continuous wave test signal or the output of a PRBS test signal, use a spectrum
analyzer on the downstream channel. The downstream carrier is enabled as a default.
The standard mode of operation is modulated signal output and the interface is active. For PRBS and
continuous wave output, the selected interface is shut down.
The functioning of the no cable downstream if-output command has not changed. The interface is shut
down.
Table 5-11 Instructions to Configure Unmodulated Test Signals
Command Purpose
Step 1
Router(config-if)# cable downstream if-output
continuous-wave
Generates an unmodulated continuous wave signal on
the downstream channel. The interface is shut down.
Step 2
Router(config-if)# no cable downstream
if-output
Stops sending test signals.
Note Remember to re-enable the interface to resume
normal operations.
Ta b l e 5 - 1 2
Command Purpose
Step 1
Router(config-if)# cable downstream if-output
prbs
Generates a PRBS test signal on the downstream
channel. The interface is shut down.
Step 2
Router(config-if)# no cable downstream
if-output
Stops sending test signals.
Note Remember to re-enable the interface to resume
normal operations.