Recall dial tone-13 dBm0 3 bursts of 0.1 s followed by a continuous tone (note c) Recall dial tone Modern PABX only (note g)-16 dBm0 3 bursts of 0.1 s followed by a continuous tone (note c) Busy ...
The standard call-waiting tone in the United States is 440 Hz for 300 ms. If the customer subscribes to Caller ID on call waiting, this tone will be followed by the dual tone (2130 + 2750 Hz) for 80 ...
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