Troubleshooting
150-231-181-01, Revision 01
46
September 7, 1999
HLU-231 List 8A
Initiating a Manual Loopback Session
A manual loopback session allows you to select any one of the HiGain GNLB loopbacks listed in
with the exception of SmartJack loopbacks, which can only be issued by inband commands.
Setting the Loopback Time-out Option
Before initiating a loopback session, verify that the Loopback Time-out parameter is set to the desired setting.
1
Use the MODE and SEL buttons as described in
“Setting Options through MODE and SEL” on page 11
.
(The Loopback Time-out parameter is also user-selectable from the System Settings screen when using a
maintenance terminal.)
2
Enter the desired setting:
•
NONE (no time-out)
•
20 minutes
•
60 minutes (default setting)
•
120 minutes
Initiating a Manual Loopback Session
To initiate a manual loopback session:
1
Press both the MODE and SEL buttons on the front panel for at least 3 seconds. The following message
appears on the front-panel display:
MAN LPBK NLO?
2
Press SEL to activate NLOC.
3
The following message appears:
Perform selected loopback
(
or
)
?
4
Type
. The display changes to
MAN LPBK NLOC
.
5
Press MODE to advance to the next available loopback (ND1? ND2? ND3? ND4? NRE? CRE? CD1? CD2?
CD3? CD4? CLO?).
6
Press SEL to activate the selected loopback. The previous loopback is terminated.
With the exception of SmartJack, any of the HiGain loopbacks can be executed using the MODE
and SEL buttons.
When executing a manual loopback session using the MODE and SEL buttons:
•
The next loopback option can be presented by pressing the MODE button, however, the
previously activated loopback remains active until the SEL button is pressed, which
activates the new loopback.
•
If neither button is pressed for a period of 30 seconds and no loopback is in effect, the
manual loopback session terminates and the display returns to normal mode.
•
If any loopback is in effect, the 30-second time-out is inhibited. The active loopback and the
manual loopback session continue until the loopback times out in accordance with the LBTO
setting.
•
Only the SMJK loopback can exist with another network loopback at any given time. In
general, it is preferable to have only one active loopback.
•
If there is an active loopback, pressing the MODE and SEL buttons for 3 or more seconds
terminates any active loopback, ends the manual loopback session and returns the display
to normal mode.
Y
N
Y
