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• 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...