Command Reference Guide

3Com Router 5000 Family and Router 6000 Family cable (CT1/PRI Interface) ● 29
Command Reference
cable (CT1/PRI Interface)
Purpose Use the cable command to set cable attenuation and length on a CT1/PRI interface
to match the distance of the transmission line.
Use the undo cable command to restore the default or long 0db.
Syntax cable { long { 0db | -7.5db | -15db | -22.5db } | short { 133ft | 266ft |
399ft | 533ft | 655ft } }
undo cable
Parameters long
Matches a 655-feet and longer transmission line. The
options for this parameter include 0db, -7.5db, -15db
and -22.5db. The attenuation parameter is selected
depending on the signal quality received at the
receiving end. In this case, no external CSU is needed.
short
Matches a transmission cable under 655 feet. The
options for this parameter include 133ft, 266ft, 399ft,
533ft and 655ft. The length parameter is selected
depending on the actual transmission segment.
Example Set the transmission cable that the CT1/PRI interface matches to 133 feet.
[3Com -T1 1/0/0] cable short 133ft
View This command can be used in the following views:
■ CT1/PRI Interface view
Description You can use this command to configure the signal waveform for transmission to
accommodate different needs.
Whether to use this command depends on the quality of the signal received by the
receiver. If the signal quality is relatively good, you can use the default setting, where
the CT1/PRI interface does not need an external CSU device.