The M bit pattern is transmitted as 01 IX where X=0 when an alarm condition exists and X=l during a normal condition. ... 3.7.4 Digital subscriber carrier terminals generally use the same basic red and yellow alarms described above for trunk terminals. ... Alarm conditions include subscriber terminal ac power failure, battery charger failure, housing door open and other ... Test codes can be generated to digitally provide 1000 hertz or another frequency at zero dBmO to align receivers.
|Title||:||Telecommunications Engineering and Construction Manual|
|Author||:||United States. Rural Electrification Administration|