Pri Interface Configuration Commands; Cable (/Pri Interface) - 3Com 3C13618 Command Reference Manual

3.3 /PRI Interface Configuration Commands

3.3.1 cable (/PRI Interface)

Syntax
cable { long { 0db | -7.5db | -15db | -22.5db } | short { 133ft | 266ft | 399ft | 533ft |
655ft } }
undo cable
View
/PRI interface view
Parameter
long: Match a transmission cable of 655 feet and above. The options for this
parameter include 0db, -7.5db, -15db and -22.5db. The attenuation parameter is
selected depending on the quality of the signal received at the receiving end. In this
case, no external CSU is needed.
short: Match a transmission cable shorter than 655 feet. The options for this
parameter include 133ft, 266ft, 399ft, 533ft and 655ft. The length parameter is
selected depending on the corresponding length of the transmission cable.
Description
Using the cable command, you can configure the attenuation or length of a
transmission cable that the /PRI interface matches. Using the undo cable command,
you can restore the default value.
By default, the attenuation of transmission cable that the /PRI interface matches is
long 0db.
This command is mainly used to configure the signal waveform at the time of
transmission to satisfy various transmitting requirements. In practice, the quality of
the signal received by the receiving end determines whether this command will be
used. If the signal quality is relatively good, use the default setting. In this case, the
/PRI interface does not need an external CSU device.
Example
# Set the length of the transmission cable that the /PRI interface matches to 133 feet.
[3Com-T1-0]cable short 133ft
Interface Management
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