Revision 01
June 12, 1997
Section 150-441-124
HiGain HLU-D41
PairGain Engineering - Plant Series
Page 29
18.10
AIS on HDSL ALRM.
The AIS on HDSL Alrm (alarm) option allows you to Enable or Disable the
AIS signal toward the CPE when the HDSL loop is not in sync or when a margin alarm occurs. The
default is Enable.
1
Press <H> in the System Settings menu.
The AIS on HDSL Alrm changes to the next available setting.
2
Repeat this process until the desired setting appears next to the AIS on HDSL Alrm option name
in the menu.
18.10.1
Enabling AIS on HDSL ALRM.
The Enable choice causes the AIS pattern to be transmitted to
the CPE when the HDSL loop experiences an out of sync (LOSW) condition or when a margin alarm
occurs. This choice causes all channels on the loop to be lost as they are replaced by the AIS pattern.
However, it does allow the downstream equipment to be made aware of the loss of the HDSL loop or
a low margin condition on the loop, which in turn alerts the maintenance personnel to the problem.
18.10.2
Disabling AIS on HDSL ALRM.
The Disable choice causes the AIS signal to be transmitted only
if the HDSL Loop is out of sync (LOSW). Margin alarms have no effect when the Disable mode is
selected. The Disable mode is the recommended setting to allow the system to operate, even with
low margin conditions, and yet continue to transmit customer data.
18.11
AIS on NREM. The AIS on NREM option allows you to Enable the AIS signal toward the CPE
when in the NREM loopback mode, or to select Disable, which transmits an LOS signal toward the
CPE when in the NREM loopback mode. The default is Enable.
1
Press <M> in the System Settings menu.
The AIS on NREM changes to the next available setting.
2
Repeat this process until the desired setting appears next to the AIS on NREM option name in the
menu.
18.12
Margin Alm Thres.
The Margin Alarm Thres (threshold) option allows you to set the margin
threshold from 0 to 15. The margin threshold, in dB, is the excess SNR relative to the SNR. A 0 dB
setting disables the option. The default is 4.
1
Press <G> in the System Settings menu.
The following prompt appears:
ENTER MINIMUM ACCEPTABLE HDSL MARGIN (0 TO 15 dB)
2
Enter the desired HDSL margin and press <Enter>.
18.13
DS0 Bandwidth.
The DS0 Bandwidth option selects the FT1 bandwidth. In the D4 or SLC-96
channel bank, the first channel of the selected bandwidth is determined by the slot occupied by the
HLU-D41. In the HRU-512, the first channel of the selected bandwidth is always channel 1.
1
Press <B> in the System Settings menu.
The DS0 Bandwidth changes to the next increment.
2
Continue to press <B> to increase the indicated bandwidth in 64 kbps increments.
The "Signaling" field adds channels each time you press B, such that 01 equates to DS0
Bandwidth 64K, 02 equates to DS0 Bandwidth 128K, etc. The maximum bandwidth setting for
the FT1 circuit is 768K (or 768 kbps).
