Cisco DNCS System Release 2.8.1 3.8.1 4.3.1 Mode D'Emploi

In general, the system sets up the QPSK bridge advanced parameters automatically, and you should not change
them. However, if you need to change any advanced parameters after you have set up the basic parameters,
keep in mind the following guidelines and contact Cisco Services if you need further assistance:

If you change any of the default parameters, you must stay within the signal capacity of your plant design.
Otherwise, the DHCTs may not be able to communicate with the DBDS. In addition, you must reboot the QPSK
bridge and wait for all corresponding DHCTs to sign on again before any changes will take effect.

1.

Do not change the Configuration File Name parameter without first consulting Cisco Services.

2.

For the Service Channel Frequency parameter, enter a value from 8 MHz to 26.5 MHz based on

your plant design.

Note: This parameter establishes the frequency that the DHCTs use to broadcast to the demodulators
on this hub.

3.

If you are not using a backup service channel, enter the same value for the Backup Service Channel

Frequency parameter that you entered for the Service Channel Frequency parameter. Otherwise, enter
a value from 8 to 26.5 MHz based on your plant design.

Note: We recommend that you not use a backup service channel. The backup service channel is used
when the service channel fails. All reverse channel messaging is sent over the channel on which the
DHCT achieves initial sign-on. If a backup service channel is in use, the DHCT may not be able to achieve
initial sign-on.

4.

For the Tuner Input Attenuator parameter, select the DHCT calibration setting based on the design

.

Note: The system will not connect to any levels that are in the fail range.

After you set up the basic parameters for the QPSK bridge, complete these steps to set up the QPSK bridge
advanced parameters.

1.

On the Set Up QPSK Modulator window, click the Advanced Parameters tab. The Advanced

Parameters window opens.

2.

In general, the system sets up the QPSK bridge advanced parameters automatically, and you should

not change them. However, if you need to change any of these parameters, refer to the guidelines listed
at the beginning of this procedure.

3.

Click Save. The system saves the advanced parameters for this QPSK bridge in the DNCS database

and closes the Set Up QPSK Modulator window. The QPSK List window updates to include the new QPSK
bridge.

4.

Add the new QPSK bridge to your network map.

5.

Do you need to add another QPSK bridge?



If yes, go back to 



If no, select File > Close to close the QPSK/CMTS List.