Table of Contents
1General
2Electricallevelsfortones
3Acousticallevelsfortones
4Dialtone
5Ringingtone
6Busytoneandcongestiontone
7Specialinformationtone
8Warningtonetoindicatethataconversationis
beingrecorded
9Payphonerecognitiontone
9.3Durationandlevel
10Callwaitingtone
11Callerwaitingtone
12Machinerecognitionoftones
AnnexA-Digitalgenerationoftones
AnnexB-Examplesforlimitationofspuriouscomponents
ofthedialtonewithrespecttointerference
withthefrequenciesrecommendedforpushbutton
telephonesetsinRecommendationQ.23
B.1MethodA(usedbyATT)
B.2MethodB(usedbytheFederalRepublicofGermany) Abstract
Defines limits and recommended values of cadences, frequencies and levels for tones used in the telephone service. Technical characteristics are relevant either for audible tones applied in the network, or for those generated at the digital terminal equipment.
