Distance Limitations - Cisco CVA122 Hardware Installation Manual

Chapter 2 Preparing for Installation
If you replace a connector, be careful not to score the center conductor. A scored conductor
Caution
can reduce or impair performance for channels broadcast between 550 and 860 MHz. If
the center conductor is too short, signals between 5 and 42 MHz might be affected.

Distance Limitations

The size of your networks and the distances between connections on the CATV network can affect the
successful installation of a Cisco CVA122/CVA122E Cable Voice Adapter, which must be within 100
miles of the CMTS. This distance can also be defined in relation to the speed of light through the
transmission network as being less than 2 msec from the CMTS to the Cisco CVA122/CVA122E Cable
Voice Adapter and back again.
Note Exceeding this distance is a violation of the DOCSIS RFI specification.
When preparing a site for network connections to the Cisco CVA122/CVA122E Cable Voice Adapter,
consider the following:
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Potential distance limitation problems in the CATV network can be reduced by doing the following:
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OL-0799-02 (05/2001)
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
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 cable voice adapter
Cisco CVA122/CVA122E Hardware Installation Guide
Site Requirements
2-7