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Wireless Intercom
A wireless intercom is a telecommunications device that enables voice communication without the need to run copper wires between intercom stations. A wired intercom system may incorporate wireless elements. There are many types of wireless intercom systems on the market. Most wireless intercom systems communicate by radio waves using one of the frequencies allotted by various government agencies. Some wireless intercom systems communicate using the 802.11 standard. There are also systems that advertise themselves as wireless, but communicate over existing building AC electrical wiring. Basic terms *Station - A wireless intercom unit. *Outdoor Intercom - This is an intercom that can be placed by a building's doors and it operates like a doorbell, but people inside can talk to the visitor. *Channels - Some wireless intercom systems have more than one channel so private conversations can occur between groups of intercoms. *Range - This is the maximum range an intercom will communic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of transmission may be divided into communication channels for multiplexing, allowing for a single medium to transmit several concurrent Session (computer science), communication sessions. Long-distance technologies invented during the 20th and 21st centuries generally use electric power, and include the electrical telegraph, telegraph, telephone, television, and radio. Early telecommunication networks used metal wires as the medium for transmitting signals. These networks were used for telegraphy and telephony for many decades. In the first decade of the 20th century, a revolution in wireless communication began with breakthroughs including those made in radio communications by Guglielmo Marconi, who won the 1909 Nobel Prize in Physics. Othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voice Communication
Speech is the use of the human voice as a medium for language. Spoken language combines vowel and consonant sounds to form units of meaning like words, which belong to a language's lexicon. There are many different intentional speech acts, such as informing, declaring, asking, persuading, directing; acts may vary in various aspects like enunciation, intonation, loudness, and tempo to convey meaning. Individuals may also unintentionally communicate aspects of their social position through speech, such as sex, age, place of origin, physiological and mental condition, education, and experiences. While normally used to facilitate communication with others, people may also use speech without the intent to communicate. Speech may nevertheless express emotions or desires; people talk to themselves sometimes in acts that are a development of what some psychologists (e.g., Lev Vygotsky) have maintained is the use of silent speech in an interior monologue to vivify and organize cognit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Wire
Copper has been used in electrical wiring since the invention of the electromagnet and the telegraph in the 1820s. The invention of the telephone in 1876 created further demand for copper wire as an electrical conductor. Copper is the electrical conductor in many categories of electrical wiring.Pops, Horace, 2008, Processing of wire from antiquity to the future, Wire Journal International, June, pp 58-66 Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Copper and its alloys are also used to make electrical contacts. Electrical wiring in buildings is the most important market for the copper industry. Roughly half of all copper mined is used to manufacture electrical wire and cable conductors. Properties of copper Electrical conductivity Electrical conductivity is a measure of how well a material transports an electric charge. This is an essential property ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intercom
An intercom, also called an intercommunication device, intercommunicator, or interphone, is a stand-alone voice communications system for use within a building, small collection of buildings or portably within a small coverage area, which functions independently of the public telephone network. Intercoms are generally mounted permanently in buildings and vehicles, but can also be detachable and portable. Intercoms can incorporate connections to public address loudspeaker systems, walkie talkies, telephones, and other intercom systems. Some intercom systems incorporate control of devices such as signal lights and door latches. Intercoms are used on a wide variety of properties; from houses that only require one connection between a resident and the property's entrance to multi-unit apartments that require intercom hardware to be installed in every individual apartment. Some are equipped with video and its wiring (electrical installation) can be connected to the outside with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wireless
Wireless communication (or just wireless, when the context allows) is the transfer of information (''telecommunication'') between two or more points without the use of an electrical conductor, optical fiber or other continuous guided transmission medium, medium for the transfer. The most common wireless technologies use radio waves. With radio waves, intended distances can be short, such as a few meters for Bluetooth, or as far as millions of kilometers for NASA Deep Space Network, deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, Mobile phone, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio ''wireless technology'' include Global Positioning System, GPS units, garage door openers, wireless Mouse (computing), computer mouse, Keyboard (computing), keyboards and Headset (audio), headsets, headphones, radio receivers, satelli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spread Spectrum
In telecommunications, especially radio communication, spread spectrum are techniques by which a signal (electrical engineering), signal (e.g., an electrical, electromagnetic, or acoustic) generated with a particular Bandwidth (signal processing), bandwidth is deliberately spread in the frequency domain over a wider frequency band. Spread-spectrum techniques are used for the establishment of secure communications, increasing resistance to natural Interference (communication), interference, Noise (electronics), noise, and radio jamming, jamming, to prevent detection, to limit Spectral flux density, power flux density (e.g., in satellite downlinks), and to enable multiple-access communications. Telecommunications Spread spectrum generally makes use of a sequential noise-like signal structure to spread the normally narrowband information signal over a relatively wideband (radio) band of frequencies. The receiver correlates the received signals to retrieve the original information ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telex Communications
Telex Communications, Inc., originally Telex Corporation, was a Burnsville, Minnesota-based manufacturer of hearing aids and audio equipment. Founded in 1936 as a maker of hearing aids, it entered the computer peripherals businesses in the 1960s. Telex Communications was structured as a subsidiary of Telex Corp in the 1970s. Telex Corp was acquired by Memorex in 1988, which renamed itself Memorex Telex NV. The hearing aid portion of Telex Corp. was subsequently spun-out in 1989 as Telex Communications, an independent company. Memorex retained Telex Corp's peripherals businesses. In February 1998 Telex Communications merged with Electro-Voice. In August 2006, the company was acquired by Germany's Bosch Group for $420 million, becoming a business unit under the name "Bosch Communications Systems". One of its chairmen, Roger Wheeler, was murdered by the Winter Hill Gang in 1981 at Southern Hills Country Club in Tulsa, Oklahoma Tulsa ( ) is the List of municipalities in O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Football
American football, referred to simply as football in the United States and Canada and also known as gridiron football, is a team sport played by two teams of eleven players on a rectangular American football field, field with goalposts at each end. The offense (sports), offense, the team with possession of the oval-shaped Ball (gridiron football), football, attempts to advance down the field by Rush (gridiron football), running with the ball or Forward pass#Gridiron football, throwing it, while the Defense (sports), defense, the team without possession of the ball, aims to stop the offense's advance and to take control of the ball for themselves. The offense must advance the ball at least ten yard, yards in four Down (gridiron football), downs or plays; if they fail, they turnover on downs, turn over the football to the defense, but if they succeed, they are given a new set of four downs to continue the Glossary of American football#drive, drive. Points are scored primarily b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Super Bowl
The Super Bowl is the annual History of the NFL championship, league championship game of the National Football League (NFL) of the United States. It has served as the final game of every NFL season since 1966 NFL season, 1966 (with the exception of the Pro Bowl between the 1967 and 2009 seasons), superseding the History of the National Football League championship, NFL Championship Game. Since Super Bowl LVI, 2022, the game has been played on the second Sunday in February. Prior Super Bowls were played on Sundays in early to mid-January from 1967 to 1978, late January from 1979 to 2003, and the first Sunday of February from 2004 to 2021. Winning teams are awarded the Vince Lombardi Trophy, named after the legendary Vince Lombardi, Packers coach who won the first two Super Bowls. Because the NFL restricts the use of its "Super Bowl" trademark, it is frequently referred to as the "big game" or other generic terms by non-sponsoring corporations. The day the game is held is common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose formal expression in terms of SI base units is 1/s or sā1, meaning that one hertz is one per second or the Inverse second, reciprocal of one second. It is used only in the case of periodic events. It is named after Heinrich Hertz, Heinrich Rudolf Hertz (1857ā1894), the first person to provide conclusive proof of the existence of electromagnetic waves. For high frequencies, the unit is commonly expressed in metric prefix, multiples: kilohertz (kHz), megahertz (MHz), gigahertz (GHz), terahertz (THz). Some of the unit's most common uses are in the description of periodic waveforms and musical tones, particularly those used in radio- and audio-related applications. It is also used to describe the clock speeds at which computers and other electronics are driven. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Voltage
In electrical engineering, low voltage is a relative term, the definition varying by context. Different definitions are used in electric power transmission and distribution, compared with electronics design. Electrical safety codes define "low voltage" circuits that are exempt from the protection required at higher voltages. These definitions vary by country and specific codes or regulations. IEC Definition The International Electrotechnical Commission (IEC) standard IEC 61140:2016 defines Low voltage as 0 to 1000 V AC RMS or 0 to 1500 V DC.IEC 61140:2016 Chapter 4.2 Other standards such as IEC 60038 defines ''supply system low voltage'' as voltage in the range 50 to 1000 V AC or 120 to 1500 V DC in ''IEC Standard Voltages'' which defines power distribution system voltages around the world. In electrical power systems ''low voltage'' most commonly refers to the mains voltages as used by domestic and light industrial and commercial consumers. "Low volta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
