5-16
Cisco uBR-3x10 RF Switch Hardware Installation and Cabling Guide
OL-1984-06
Chapter 5 Cabling the RF Switch With the Cisco uBR7246VXR CMTS
Connecting the Cables (Cisco uBR-MC28x Line Card)
Connecting the Cables (Cisco uBR-MC28x Line Card)
This section describes one method of cable management using the sample configuration for the
Cisco uBR7246VXR with the Cisco uBR-MC28x (C, U, X) cards installed.
The RF cables are connected to the CMTS, PROTECT, and CABLE PLANT sections on the rear panel
of the two Cisco uBR 3x10 RF Switches using header blocks. There are:
• Thirty-two RF connection groups under CMTS—Each line card is two working groups. These
groups of RF cables connect to cable interface line cards and to IF-to-RF upconverters.
• Eight RF connection groups under PROTECT—These groups of RF cables connect to cable
interfaces designated as the protect interface.
• Thirty-two RF connection groups under CABLE PLANT—These groups of RF cables connect to
the coaxial or fiber-optic cable transceivers (in the upstream direction) and IF-to-RF upconverters
(in the downstream direction) at the cable headend or HUB.
Note A connection group is a MAC domain which includes a downstream and it’s associated
upstreams.
Cabling the Working Line Card (VXR1–VXR4)
This section describes cabling the working line cards from the Cisco uBR7246VXR routers to the RF
switch.
Equipment
• 16 cable bundles—4 per router, one per card (F-connector to MCX connector—multicolor)
• 16 header blocks (installed)
To cable the working line cards, complete the following steps. Refer to Table 5-11 for the color scheme.
Step 1 Connect the cables to the upstream ports (US0–US3, US0–US3) on the line cards in VXR1. Tighten the
F-connectors to a value between 10 (recommended) and 15 (maximum) inch-pounds (1.1298 nm and
1.7339 nm).
Note Cable and connect to the RF switch, one card at a time. See the “Installing the Header Blocks on
the Cisco uBR 3x10 RF Switch” section on page 5-7, if necessary.
Step 2 Secure the cables with cable wrap, and run the cable bundles up the left side of the equipment rack.
Step 3 Install the cables in the CMTS header block in the order that they were mapped.
a. Carefully follow the cabling directions shown in Table 5-12 and Table 5-13 on page 5-18 for cable
locations on the RF switches and the appropriate header block.
Note LC1 and LC2 go to RF switch 2 (RFS-2); LC3 and LC4 go to RF switch 1(RFS-1).
b. Push the MCX connector into the hole in the header block until you can feel it snap into place.
c. Gently wiggle the connector to make sure that the connection is secure.
