Line Build Out (Lbo) Switches; Figure 11. Lbo Switches - ADC Kentrox 78220 Operator's Manual

Line Build Out (LBO) Switches

The setting for Line Build Out (LBO) to the network is determined by
the carrier and is based on the line distance to the nearest T1 repeater.
The different LBO settings allow the user to adjust the attenuation of
the signal transmitted out the network port of the D-SERV DSU/CSU.
The default setting is 0.0 dB. Your T1 service provider will be able to
tell you if a non-default setting is required in your application.
WARNING:
Improper setting of the LBO switches may cause
interference with other telephone company
services. Proper setting of the LBO switches will
ensure reliable operation both for you and for
others.
If it is necessary to modify the LBO settings, first locate the switches
on the right side of the D-SERV DSU/CSU towards the rear as you are
facing the unit. Using a narrow, non-conductive device, set the
switches to the appropriate setting (0.0 dB, -7.5 dB, -15.0 dB, or -22.5
dB). For example, to set the LBO to -22.5 dB, set both switches to the
right.

Figure 11. LBO Switches

FRONT
0 db -7.5 db 0 db
Operator's Manual
-15 db
19