CCITT Rec. Q.400 Sup.5 (11/1988) – LINE SIGNALLING (ANALOGUE VERSION) WITH METERING
1 General
2 Line conditions
3 Clauses for exchange line signalling equipment
3.1 Recognition time for transition of signalling condition
3.2 Normal operating conditions
3.2.1 General
3.2.2 Metering
3.2.3 Forced release (see Figures 1 and 2)
4 Mode of operation of interruption control
4.1 General
4.2 Mode of operation of interruption control at the incoming end (transmission interrupted in the forward directio...
4.3 Mode of operation of the interruption control at the outgoing end (transmission in the backward direction inter...