Radioteletype (RTTY) is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations connected by radio rather than a wired link. Radioteletype evolved from earlier landline teleprinter operations that began in the mid-1800s. The US Navy Department successfully tested printing telegraphy between an airplane and ground radio station in 1922. Later that year, the Radio Corporation of America successfully tested printing telegraphy via their Chatham, Massachusetts, radio station to the R.M.S. Majestic. Commercial RTTY systems were in active service between San Francisco and Honolulu as early as April 1932 and between San Francisco and New York City by 1934. The US military used radioteletype in the 1930s and expanded this usage during World War II. From the 1980s, teleprinters were replaced by personal computers (PCs) running software to emulate teleprinters.
In telecommunications, an acoustic coupler is an interface device for coupling electrical signals by acoustical means—usually into and out of a telephone.
In telecommunications, a customer-premises equipment or customer-provided equipment (CPE) is any terminal and associated equipment located at a subscriber's premises and connected with a carrier's telecommunication circuit at the demarcation point ("demarc"). The demarc is a point established in a building or complex to separate customer equipment from the equipment located in either the distribution infrastructure or central office of the communications service provider.
A telecommunications device for the deaf (TDD) is a teleprinter, an electronic device for text communication over a telephone line, that is designed for use by persons with hearing or speech difficulties. Other names for the device include teletypewriter (TTY), textphone, and minicom.
SRI International (SRI) is an American nonprofit scientific research institute and organization headquartered in Menlo Park, California. The trustees of Stanford University established SRI in 1946 as a center of innovation to support economic development in the region.
A telecommunications relay service, also known as TRS, relay service, or IP-relay, or Web-based relay service, is an operator service that allows people who are deaf, hard of hearing, deafblind, or have a speech disorder to place calls to standard telephone users via a keyboard or assistive device. Originally, relay services were designed to be connected through a TDD, teletypewriter (TTY) or other assistive telephone device. Services gradually have expanded to include almost any real-time text capable technology such as a personal computer, laptop, mobile phone, PDA, and many other devices. The first TTY was invented by deaf scientist Robert Weitbrecht in 1964. The first relay service was established in 1974 by Converse Communications of Connecticut.
The Carterfone is a device invented by Thomas Carter. It manually connects a two-way radio system to the telephone system, allowing someone on the radio to talk to someone on the phone. This makes it a direct predecessor to today's autopatch.
106 Text Emergency Call, commonly known as simply 106, is the Australian national emergency telephone number to be used in life-threatening or time critical situations for those with a speech and / or hearing impairment who use telecommunications device for the deaf. It is run by the emergency telephone operator for the National Relay Service (NRS); formerly the Australian Communications Exchange (ACE), a non-profit organisation that provided the relay services component for the NRS. 106 can only be used by people with a TTY / textphone, or a computer with terminal software and a modem. 106 calls are given priority over other calls handled by the National Relay Service. 106 is a free-to-call number.
The history of telecommunication began with the use of smoke signals and drums in Africa, Asia, and the Americas. In the 1790s, the first fixed semaphore systems emerged in Europe. However, it was not until the 1830s that electrical telecommunication systems started to appear. This article details the history of telecommunication and the individuals who helped make telecommunication systems what they are today. The history of telecommunication is an important part of the larger history of communication.
George H. Sweigert (1920–1999) is credited as the first inventor to patent the cordless telephone.
This history of the telephone chronicles the development of the electrical telephone, and includes a brief overview of its predecessors. The first telephone patent was granted to Alexander Graham Bell in 1876.
Underwater acoustic communication is a technique of sending and receiving messages below water. There are several ways of employing such communication but the most common is by using hydrophones. Underwater communication is difficult due to factors such as multi-path propagation, time variations of the channel, small available bandwidth and strong signal attenuation, especially over long ranges. Compared to terrestrial communication, underwater communication has low data rates because it uses acoustic waves instead of electromagnetic waves.
A modulator-demodulator or modem is a computer hardware device that converts data from a digital format into a format suitable for an analog transmission medium such as telephone or radio. A modem transmits data by modulating one or more carrier wave signals to encode digital information, while the receiver demodulates the signal to recreate the original digital information. The goal is to produce a signal that can be transmitted easily and decoded reliably. Modems can be used with almost any means of transmitting analog signals, from light-emitting diodes to radio.
James Carlyle Marsters was a deaf orthodontist in Pasadena, California who in 1964 helped invent the first teletypewriter device capable of being used with telephone lines. The device made communication by telephone possible for the deaf. Although Robert Weitbrecht did much of the actual design work, Marsters promoted the device's use.
Paul Taylor was an American engineer, a pioneer in development of telecommunications devices for the deaf. He also enjoyed a kind of celebrity status because of his central role in the award-winning documentary Hear and Now. The film by daughter Irene Taylor Brodsky chronicles the before and after experiences of her parents, Paul and Sally Taylor, both of whom underwent cochlear implant surgeries in their mid-60s after a lifetime of deafness.
Weitbrecht Communications, Inc. (WCI) is a Santa Monica, California company that specializes in providing products for deaf people. The company was founded as Applied Communications around 1965 by Robert Weitbrecht and James C. Marsters based on Weitbrecht's invention of the teleprinter at SRI International.
The Laurent Clerc Award is an annual honor bestowed by Gallaudet University's Alumni Association to recognize a deaf person for "his or her outstanding contributions to society," and specifically to honor their achievements in the interest of deaf people. It is named for Laurent Clerc (1785-1869). It has been given to notable scientists and inventors, such as deaf scientist Robert Weitbrecht, to honor his contributions in developing the teleprinter and an acoustic coupler for the early computer modem. It is awarded by Gallaudet University's Alumni Association through its Laurent Clerc Cultural Fund.
Echo suppression and echo cancellation are methods used in telephony to improve voice quality by preventing echo from being created or removing it after it is already present. In addition to improving subjective audio quality, echo suppression increases the capacity achieved through silence suppression by preventing echo from traveling across a telecommunications network. Echo suppressors were developed in the 1950s in response to the first use of satellites for telecommunications.
Anderson Jacobson, also known for a time as CXR Anderson Jacobson and today as CXR Networks, is a vendor of communications equipment. Anderson Jacobson was an early manufacturer of acoustic modems and was spun off from SRI International. In the 1970s and 1980s, the company manufactured modems, some intended for consumers. The company was acquired by CXR Telecom in 1988, at which time The Times was following Anderson Jacobson's earnings reports. The flow of new products continued.
