Multi-frequency signaling (MF) is a group of signaling methods that use a mixture of two pure tone (pure sine wave) sounds. Various MF signaling protocols were devised by the Bell System and CCITT.

Dual tone multi-frequency (DTMF) is the sounds or tones generated by a telephone when the numbers are pressed. These tones are transmitted with the voice channel. DTMF is used to control automated equipment and signal user intent, such as the number they wish to dial. Each key has two tones at specific frequencies.

DTMF is used in ham radio in applications such as IRLP and Echolink, as a means to dial outside numbers via phone patch and as a means for repeater owners to configure the system remotely. It is sometimes known as tone dialing and allows the user to send a series of tones that activate or disable a remote repeater or service.

DTMF Meaning: What Is DTMF and How Does It Work? In the 1950s, the Bell System, led by AT&T, began research into different transmission methods for dialing phone numbers and connecting phone calls. A method they developed, called MF (multi-frequency) signaling, was so successful in connecting distant telephone exchanges for long-distance calls ...

2023年9月18日 · DTMF, which stands for Dual-tone Multi-Frequency, is a technology used in telephony for transmitting and decoding digits using a keypad or touchtone buttons on a phone. DTMF technology has several advantages that make it a …

2021年11月25日 · DTMF is a signaling mode used for a variety of purposes. It's most known for telephony dialing, but is in use for many different applications such as DTMF paging for DTMF-enabled VHF Very High Frequency (30-300 MHz) / UHF Ultra High Frequency (300-3000 MHz) radios and as a marker on broadcasting stations for switching between regional and local ...

DTMF, or Dual-Tone Multi-Frequency tones, are in-band telecommunications signals sent over voice frequencies. Commonly used over telephone lines, DTMF tones are also commonly called Touch Tones.

What is Dual Tone Multi-Frequency? The DTMF (dual tone multi-frequency) is one kind of signaling system intended for identifying a push button on a DTMF keypad. A key can be formed by combining two sine wave tones. These tones are the frequencies of rows as well as column which are represented on the keypad of the DTMF.

2022年11月18日 · Dual-tone multi-frequency (DTMF) produces touch tone sounds heard when pressing a number on a phone’s keypad. When you press a number key, DTMF sends the following: command to the switch. And it does this by sending two tones – a high- and low-frequency tone – for every number key pressed.

2023年3月28日 · DTMF (Dual-tone multi-frequency) is a signaling technique used in telecommunication systems to transmit digits, letters, and special characters over the voice channel. The technology was first introduced in the 1960s and has since become widely used in telephony, radio communication, and other applications.