ADTRAN 1200275L1, Руководство пользователя

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Chapter 8. Configuring DBU Options
61200275L1-1 TSU IQ+ User Manual 8-9
Physical Layer Options
The following sections describe the P
HYSICAL
L
AYER
O
PTIONS
available for the PRI DBU card.
Line Code
Set the line coding of the PRI DBU card to B8ZS for PRI
applications.
Clock Source
Set the clock source to be derived from the network or from the
unit’s internal clock. The selected clocking option designates the
clock source for transmission. Clocking necessary for receiving data
is recovered from incoming data. This option is most commonly set
to
N
ETWORK
.
Line Buildout
Select the output level (in dB) for the PRI DBU card interface.
Choices:
A
UTO
, 0 , 7.5 , 15.0 , and 22.5 dB .
Rx Gain
Select the desired receiver sensitivity setting. The factory default
setting is
N
ORMAL
, which is adequate for most applications. The
E
XTENDED
setting should be used only in applications where the
N
ORMAL
setting is not sufficient. If the receive signal strength is less
than 30 dB, choose E
XTENDED
.
Start Channel
Select the channel in which the T1 stream starts. The setting must
be consistent with the carrier if using a public network.
Number of Channels
Select the number of DS0s (channels) that are to be used. Note that
the PRI card uses one DS0 per connected call.
Tx Yellow Alarm
Set TX Y
EL
A
LARM
to Y
ES
to transmit yellow alarms when a red
alarm is detected. Set this entry to N
O
to avoid transmitting yellow
alarms upon red alarm detection.