97
The following diagram shows the duration and intervals of the individual audio sig-
nals and ringer cadences.
Audio Signals / Ringer Cadences
Audio signals
Time in seconds
Ring tone
Busy tone
Internal dialling tone
External dialling tone
Positive acknowledgement tone
Negative acknowledgement tone
Internal special dialling tone
External special dialling tone
Call-waiting tone
Rings
External call
Internal call
Recall
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Appendix