Cisco uBR-3x10 Hardware Installation And Cabling Manual page 22

Hardware Component Descriptions
Downstream Switch Module
•
Three downstream (high-frequency) switch modules are used in the Cisco uBR 3x10 RF Switch. The
module operates from 54 to 860 MHz. Each downstream switch module has ten 75-ohm inputs accessed
through the CABLE PLANT MCX connectors on the backpanel of the RF switch. During normal system
operation, the downstream switch module switches all direct traffic to their respective default
termination interfaces.
See
Note
for more cabling information.
The downstream switch module accepts signal inputs (eight) from the power combiner and combines one
of the eight to a protect output. Alternately, the switch splits the inputs into two groups of four and then
selects one input (in the group of four) to combine with the protect input. The relays are
electromechanical, latching relays that are controlled through an I
a minimum of 60 dB of isolation from connector port to connector port.
Figure 1-6
Each downstream switch board contains a set of four LEDs that indicates the working status of the port
as described in
Table 1-3
LED Name
Protect 1
Protect 2
Error 1
Error 2
Cisco uBR-3x10 RF Switch Hardware Installation and Cabling Guide
1-8
Cisco part number 74-2623-01 (See
Chapter 4, "Cabling the RF Switch With the Cisco uBR10012 CMTS Cable Interface Line Cards,"
Downstream Switch PCB Assembly
Captive screw
Table 1-3 on page
Downstream Switch Board LED Descriptions
Color
Green/Yellow
Green/ Yellow
Off/Yellow
Off/Yellow
Figure 1-6 on page
1-8.
Description
Indicates CMTS/PROTECT 1
Indicates CABLE PLANT/PROTECT 2
Indicates a channel problem 1
Indicates a channel problem 2
Chapter 1 Cisco uBR-3x10 RF Switch Overview
1-8)
2
C interface. The switch card provides
Captive screw
OL-1984-06