Dual-tone multi-frequency signaling (DTMF) is a telecommunication signaling system using the voice-frequency band over telephone lines between telephone equipment and other communications devices and switching centers. DTMF was first developed in the Bell System in the United States, and became known under the trademark Touch-Tone for use in push-button telephones supplied to telephone customers, starting in 1963. DTMF is standardized as ITU-T Recommendation Q.23. It is also known in the UK as MF4.
Throughout the 20th century, telephone switchboards were devices used to connect circuits of telephones to establish telephone calls between users or other switchboards. The switchboard was an essential component of a manual telephone exchange, and was operated by switchboard operators who used electrical cords or switches to establish the connections.
A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from Greek: τῆλε and φωνή, together meaning distant voice. A common short form of the term is phone, which came into use almost immediately after the first patent was issued.
In telephony, ringdown is a method of signaling an operator in which telephone ringing current is sent over the line to operate a lamp or cause the operation of a self-locking relay known as a drop.
A blue box is an electronic device that produces tones used to generate the in-band signaling tones formerly used within the North American long-distance telephone network to send line status and called number information over voice circuits. This allowed the user, referred to as a "phreaker", to surreptitiously place long-distance calls that would be billed to another number or dismissed entirely as an incomplete call. A number of similar "color boxes" were also created to control other aspects of the phone network.
Emile Berliner originally Emil Berliner, was a German-American inventor. He is best known for inventing the lateral-cut flat disc record used with a gramophone. He founded the United States Gramophone Company in 1894; The Gramophone Company in London, England, in 1897; Deutsche Grammophon in Hanover, Germany, in 1898; and Berliner Gram-o-phone Company of Canada in Montreal in 1899.
An answering machine, answerphone or message machine, also known as telephone messaging machine in the UK and some Commonwealth countries, ansaphone or ansafone, or telephone answering device (TAD), is used for answering telephones and recording callers' messages. If a phone rings a number of times predetermined by the phone's owner, and nobody is present to answer the incoming call, the answering machine will activate and play either a generic announcement or the voice of the person being called announcing that nobody is able to come to the phone at the moment. Following the announcement is a beeping tone which prompts the caller to record a message after the tone concludes.
A voicemail system is a computer-based system that allows users and subscribers to exchange personal voice messages; to select and deliver voice information; and to process transactions relating to individuals, organizations, products, and services, using an ordinary phone. The term is also used more broadly to denote any system of conveying a stored telecommunications voice messages, including using an answering machine. Most cell phone services offer voicemail as a basic feature; many corporate private branch exchanges include versatile internal voice-messaging services, and *98 vertical service code subscription is available to most individual and small business landline subscribers.
A boom operator is a core role in the sound department of a film production, who works with the production sound mixer and utility sound technician. The principal responsibility of the boom operator is microphone placement, usually using a boom pole with a microphone attached to the end, their aim being to hold the microphone as close to the actors or action as possible without allowing the microphone or boom pole to enter the camera's frame.
The public switched telephone network (PSTN) provides infrastructure and services for public telecommunication. The PSTN is the aggregate of the world's circuit-switched telephone networks that are operated by national, regional, or local telephony operators. These consist of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all interconnected by switching centers which allow most telephones to communicate with each other.
A speaking clock or talking clock is a live or recorded human voice service, usually accessed by telephone, that gives the correct time. The first telephone speaking clock service was introduced in France, in association with the Paris Observatory, on 14 February 1933.
A business telephone system is a multiline telephone system typically used in business environments, encompassing systems ranging in technology from the key telephone system (KTS) to the private branch exchange (PBX).
A sound-powered telephone is a communication device that allows users to talk to each other with the use of a handset, similar to a conventional telephone, but without the use of external power. This technology has been used since at least 1944 for both routine and emergency communication on ships to allow communication between key locations on a vessel if power is unavailable. A sound-powered phone circuit can have two or more stations on the same circuit. The circuit is always live, thus a user begins speaking rather than dialing another station. Sound-powered telephones are not normally connected to a telephone exchange.
The Mobile Telephone Service (MTS) was a pre-cellular VHF radio system that linked to the Public Switched Telephone Network (PSTN). MTS was the radiotelephone equivalent of land dial phone service.
Audichron Company was a company founded in the 1930s by John Franklin in Doraville, Georgia, to produce the Audichron, a talking clock. By the 1970s, there were thousands of Audichron time-of-day announcers in use all over the world. Audichron had also developed a machine to announce the temperature. During the 1970s and 1980s, Audichron began to manufacture other kinds of equipment besides time and temperature machines.
Audichron was a talking clock, or a time announcer which was developed and produced by the Audichron Company, starting in the 1930s. There were several types of Audichron machines including the stand time piece (STM), M12, temperature machine (TEMP) and the Comparator.
Pat Trumble Fleet is an American voice actress known as the registered voice of AT&T. Widely recognized for the tens of thousands of recordings she has made for US telephone companies such as AT&T, Verizon, Qwest, the former Bell System companies, and others since 1981, she is still most recognized as the person who says "AT&T" in the company's sound trademark played prior to any operator assisted or credit card paid call, and on answer when calling AT&T customer service numbers.
A telephone exchange, telephone switch, or central office is a telecommunications system used in the public switched telephone network (PSTN) or in large enterprises. It interconnects telephone subscriber lines or virtual circuits of digital systems to establish telephone calls between subscribers.
A dial-a-joke is a telephone service that users can call to listen to previously recorded jokes. Jokes are recorded on an automatic answering machine. In the past, many jokes were recorded on cassette tape and then played sequentially, each caller hearing the next joke on the tape. Modern touch tone phones allow callers to select different joke types: knock-knock, joke of the day, professional humor, random, etc.
The Panel Machine Switching System is a type of automatic telephone exchange for urban service that was used in the Bell System in the United States for seven decades. The first semi-mechanical types of this design were installed in 1915 in Newark, New Jersey, and the last were retired in the same city in 1983.
