Modem User Manual

Site Requirements
Cisco uBR904 Cable Modem Installation and Configuration Guide
2-8
We recommend that you replace any cable that is in question to begin the installation with
clean, two-way digital data transmission media. If the cable is of high-quality and was
recently installed, replacing the connectors with high-quality connectors can also improve
performance.
Distance Limitations
The size of your networks and the distances between connections on the CATV network
can affect the successful installation of a Cisco uBR904 cable modem.
When preparing a site for network connections to the Cisco uBR904 cable modem, you
must consider several factors related to the cabling:
• The number of amplifiers from the installation site to the nearest node
• The number of outlets and amplifiers at the installation site
• Cable pinouts if you plan to build your cables
Potential distance limitation problems in the CATV network can be reduced by ensuring the
following factors:
• A correct, linear unity gain two-way sweep procedure is in place
• Industry-standard configuration practices are used at the headend
• The downstream frequency is known at the time of installation
• The absolute downstream signal level can be measured where it enters the
Cisco uBR904 cable modem
Caution If you replace a connector, be careful not to score the center conductor. A
scored conductor can reduce or impair performance for channels broadcast between 550
and 860 MHz.