AM64/128A User Manual

Alarm Status

 

 

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

 

 

15

Page 15
Image 15
American Telecom AM64/128A manual Alarm Status, No Alarm No Signal Receiving AIS No Alignment, LOS/CD Fail