Intellectual Property Rights
Foreword
Introduction
1 Scope
2 References
3 Definitions, symbols and abbreviations
3.1 Definitions
3.2 Symbols
3.3 Abbreviations
4 General
5 Physical connections
5.1 Mechanical aspects
5.2 Support of more than one terminal
6 DC feed conditions
6.1 Polarity
6.2 Quiescent state
6.3 Loop current
7 Seize signal
7.1 Must not seize condition
7.2 Must seize condition
8 Clear signal
8.1 Clear signal generated by TE
8.2 Clear indication from the network
8.3 Seizing the line for a new call
9 Impedance
9.1 Impedance at the R interface
9.2 Balance about earth
10 Transmission
10.1 Relative level
10.2 Variation of gain with input level
10.3 Frequency response
10.4 Coding law
10.5 Noise
10.6 Echo and stability
10.7 Crosstalk
10.8 Total distortion including quantizing distortion
11 DTMF Dialling
12 Ringing
12.1 Ringing drive capability
12.2 Ring cadence
12.3 Ring trip
12.4 False ring trip
13 Supervisory signals
13.1 Supervisory tones
13.2 Tone levels
13.3 Cadences and frequencies
14 Optional functions
14.1 Loop disconnect dialling
14.2 Register recall
14.3 Metering
14.4 Supplementary and other enhanced services
14.5 Polarity reversal
14.6 End of call signal ("K-break")
14.7 Payphones
Annex A (informative): Test set-up for the change from DC
to ringing voltage
Annex B (informative): Bibliography
History