Filter
Top Products
Configuring and Managing T1 Digital Line Cards 247
The NBX system now begins to create the group. If you connect the
telephone company’s T1 line to the T1 Digital Line Card, or if you connect
a loopback cable to the T1 card, the Nominal light turns on.
Verifying T1 Group Membership (DS1)
To verify that all channels are in the Member List of a T1 Digital Line Card:
1 On the Digital Line Cards tab, select T1 Group List from the Select Device
Type list and click Apply.
2 From the list, select the group you want.
3 Click Membership. The Manage Group Membership dialog box appears.
4 Scroll through the Member List to verify that all 23 channels are present
for each T1 Digital Line Card in the system.
Completing the T1 Configuration (DS1)
To complete the T1 installation:
1 On the Digital Line Cards tab, select T1 Channel List from the Select
Device Type list and click Apply.
2 Wait approximately 30 seconds for the status of each channel to change
from Ready to Idle.
Click Apply to refresh the list of channels and to see the updated status. If
you have connected the Telephone company’s T1 line to the T1 Digital
Line Card or if you have connected a loopback connector to the T1 card,
the Nominal status light on the front panel of the T1 board should now
turn on (solid green). If the Nominal status light does not turn on and you
have the telephone company’s T1 line connected, disconnect the T1 line
and connect a loopback connector. If the Nominal light now turns on,
contact the telephone company for assistance with the T1 line. If the
Nominal light does not turn on, contact 3Com Technical Support.
Enabling and Disabling Echo Cancellation
There are two situations in which it may be desirable to disable echo
cancellation on a T1 Digital Line Card.
■ An NBX system is connected to a telephone carrier (Central Office) by
a T1 Digital Line Card, and the telephone carrier guarantees to provide
echo cancellation on all channels, all of the time.
■ Two NBX systems are connected together directly using T1 Digital Line
Cards and the network between the two is completely composed of
digital circuitry, thus eliminating sources of echo.