American Telecom AM64/128A - Manual (Page 15)

AM64/128A User Manual Alarm Status
15
5.3.2 Alarm Status
The possible messages for this item are:
S > No Alarm
S > No Signal
S > Receiving AIS
S > No Alignment
The S > No Signal display indicates that the transmission system cannot find a signal to lock on to.
Possible causes are:
(a) Broken or defective line
(b) Both ends master, or both ends slave
(c) Incorrect line rate
(d) Line attenuation / noise level too high
The S > Receiving AIS display indicates that an AIS (Alarm Indication Signal) pattern is being
received from the line. This should not normally occur in a BBM to BBM link, but can be generated if the
master BBM is in 64k mode whilst sending binary 1’s.
If the alignment pattern from the line cannot be locked onto, the display reads: S > No Alignment
Possible causes are :
(a) Line attenuation / noise level too high. (b) Incorrect set up of X.50 modes.
S > LOS/CD Fail This is a G.703 Interface message display indicating that there is loss of
synch or line break transmission fault, and there is no G.703 receive signal present.
S > CD Fail This is a G.703 Interface message display indicating that there is no G.703
receive signal present, but that the transmission circuit is in synchronisation.
S > Line LOS This is a G.703 Interface message display indicating that there is loss of synch
or a line break transmission fault, but there is a G.703 receive signal present.
If none of these conditions apply then the message is: S > No Alarm