It does this by sending two tones for every number pushed - one high frequency and one low frequency.ĭual tone multi frequency (DTMF) has an important use in call centers, as many interactive voice response (IVR) systems use dual tone multi frequency (DTMF) as a way for callers to navigate their menus. It signals the phone company that you want to make a call and sends a command to the switch.
Changing the DTMF Duration changes the duration of each tone and silence while retaining the ratio between them.įor example, if you generate four tones in a sequence lasting four seconds, choosing a duty cycle of 50% in order to make the tones and silences of equal duration, the four tones and the three silences between them will all be 571 milliseconds long.What is Dual Tone Multi Frequency (DTMF)?ĭual tone multi frequency (DTMF) is a technology used with touch tone phones, best known to users as the sound made when pressing a number key. This ratio is displayed underneath the slider as the "duty cycle" along with the resulting duration of each tone and silence. Use the slider to select the ratio between the length of each tone in the series and the length of the silences between them. When replacing a selection region, Duration always displays the exact duration of that selection to the nearest audio sample.However, your last entered Duration is always remembered. When generating at the cursor, Duration initializes to 30.000 seconds (except for the DTMF generator which defaults to 1.000 second).You can also increment a highlighted digit with keyboard Up or Down arrow instead of typing. If the required first digit is not highlighted, use Left or Right arrow on your keyboard to move to the first digit, then type. If the first digit you want is highlighted, just type the whole number. Type (or use the keyboard arrows) to enter the required Duration. Permitted values are between 0 (silence) and 1 (the maximum possible volume without clipping), with a default of 0.8. Lets you type an amplitude value for the loudness of the generated audio. You can also enter the four "priority" tones used by the US Military (upper case A, B, C and D).
DTMF sequenceįor each tone you wish to generate, enter numbers from 0 to 9, lower case letters from a to z, and the * and # characters. DTMF Tones generates dual-tone multi-frequency (DTMF) tones like those produced by the keypad on telephones.
0 kommentar(er)
