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Cisco Cable Clock Card Hardware Installation Guide for the Cisco uBR7246VXR Universal Broadband Router
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Overview
This chapter describes the Cisco Cable Clock Card and contains the following sections:
•
Clock Card Overview, page 1-1
•
Clock Source Overview, page 1-2
•
Interface Specifications and Pinouts, page 1-3
•
LEDs, page 1-4
•
Clock Card Location in the Cisco uBR7246 VXR Chassis, page 1-5
Clock Card Overview
The Cisco Cable Clock Card (see
Figure 1-1
) is a dual-port field-replaceable component that is designed
to provide a reliable national clock signal to your Cisco uBR7246 VXR universal broadband router. The
primary and secondary DB-15 interfaces on the front of the clock card connect to external T1 clock
signal sources.
When installed in the Cisco uBR7246 VXR chassis, the clock card can propagate a national clock signal
throughout the router’s midplane by locking onto an external T1 signal originating over the PSTN,
locking onto a T1 clock signal originating from a port adapter installed in the same chassis, or by
connecting to a Global Positioning System (GPS) receiver generating a T1 clock signal.
Figure 1-1
Clock Card—Faceplate View
Caution
Do not attempt to remove or install the clock card unless you have first powered off the
Cisco uBR7246 VXR.
Note
The Cisco Cable Clock Card does not support an E1 interface.
31495
uBR - CLK-T1
ENABLE
HOLDOVER
FREERUN
FAULT
LOS
PRI
SEC
ACTIVE
