NetComm 4-port and 8-port Gateways Gateway Series Reference Manual page 53

Once detection of a busy tone is in progress, the system will dial the number to be tested (in this case
36008913). After it rings pick up the phone and enter"#", then hang up. The system will then detect a
busy tone automatically.
After detecting it will be as below:
SmartVoice Gateway(s) User Guide
YML83 Rev
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