DTMF Operation
When DTMF is enabled, DTMF tones can be sent using the Keypad from the Main
Channel screen. Pressing 0...9, * and # will send the associated tones.
The tone period and gap are set using the FPP.
DTMF is only applicable to Analogue mode, and can only be enabled using the FPP.
Document Number: TNM-U-E-0145 Issue: 1.0 Page 35