DTMF Tones

This App generates DTMF Tones of a 4x4 keypad and It can be used in Robotics and Embedded Systems also .

What is DTMF?

Dual-tone multi-frequency signaling (DTMF) is used for telecommunication signaling over analog telephone lines in the voice-frequency band between telephone handsets and other communications devices and the switching center. The version of DTMF that is used in push-button telephones for tone dialing is known as Touch-Tone.

How it Works?

The DTMF keypad is laid out in a 4×4 matrix in which each row represents a low frequency and each column represents a high frequency. Pressing a single key sends a sinusoidal tone for each of the two frequencies. For example, the key 1 produces a superimposition of tones of 697 and 1209 hertz (Hz). Initial pushbutton designs employed levers, so that each button activated two contacts. The tones are decoded by the switching center to determine the keys pressed by the user.

</div> <div class="id-app-translated-desc" style="display:none">这个程序生成一个4×4键盘的DTMF音，它可以在机器人被用来与嵌入式系统也。

什么是DTMF？

双音多频（DTMF）用于通过在话音频带电话手机和其它通信设备和交换中心之间的模拟电话线路的电信信令。 DTMF的用于在按键电话音频拨号的版本被称为触摸音。

它是如何工作的？

DTMF键盘被布置在一个4×4矩阵，其中每一行代表一个低频，每一列代表一个高频。按一个键发送的正弦音调为每两个频率。例如，密钥1产生的697和1209赫兹（Hz）的音调的叠加。初始按钮的设计采用杠杆，以使每个按钮来激活的两个触点。该音调是由交换中心解码以确定由用户按下的键。</div> <div class="show-more-end">