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Radioteletype
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 ( RCA) successfully tested printing telegraphy via their Chatham, Massachusetts, radio station to the RMS ''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. The term radioteletype is used to describe both the or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teleprinter
A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point (telecommunications), point-to-point and point-to-multipoint communication, point-to-multipoint configurations. Initially, from 1887 at the earliest, teleprinters were used in telegraphy. Electrical telegraphy had been developed decades earlier in the late 1830s and 1840s, then using simpler Morse key equipment and telegraph operators. The introduction of teleprinters automated much of this work and eventually largely replaced skilled labour, skilled operators versed in Morse code with Data entry clerk, typists and machines communicating faster via Baudot code. With the development of early computers in the 1950s, teleprinters were adapted to allow typed data to be sent to a computer, and responses printed. Some teleprinter models could also be used to create punched tape for Compute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Creed Model 6S-2 Paper Tape Reader
A creed, also known as a confession of faith, a symbol, or a statement of faith, is a statement of the shared beliefs of a community (often a religious community) which summarizes its core tenets. Many Christian denominations use three creeds: the Niceno-Constantinopolitan Creed, the Apostles' Creed and the Athanasian Creed. Some Christian denominations do not use any of those creeds. The term ''creed'' is sometimes extended to comparable concepts in non-Christian theologies. The Islamic concept of ''ʿaqīdah'' (literally "bond, tie") is often rendered as "creed". History The earliest known creed in Christianity, "Jesus is Lord", originated in the writings of Paul the Apostle. One of the most significant and widely used Christian creeds is the Nicene Creed, first formulated in AD 325 at the First Council of Nicaea to affirm the deity of Christ and revised at the First Council of Constantinople in AD 381 to affirm the trinity as a whole. The creed was further affirmed in 43 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Line Level
Line level is the specified Audio power, strength of an audio signal used to transmit analog (signal), analog sound between audio components such as compact disc, CD and Digital Versatile Disc, DVD players, television sets, audio amplifiers, and mixing consoles. Generally, line level signals sit in the middle of the hierarchy of signal levels in audio engineering. There are weaker signals such as those from microphones (Mic Level/Microphone Level) and Pick up (music technology), instrument pickups (Instrument Level), and stronger signals, such as those used to drive headphones and loudspeakers (Speaker Level). The "strength" of these various signals does not necessarily refer to the output voltage of the source device; it also depends on its output impedance and output power capability. Consumer electronic devices concerned with audio (for example Sound card#General characteristics, sound cards) often have a connector labeled ''line in'' and/or ''line out''. ''Line out'' provides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boolean Algebra
In mathematics and mathematical logic, Boolean algebra is a branch of algebra. It differs from elementary algebra in two ways. First, the values of the variable (mathematics), variables are the truth values ''true'' and ''false'', usually denoted by 1 and 0, whereas in elementary algebra the values of the variables are numbers. Second, Boolean algebra uses logical operators such as Logical conjunction, conjunction (''and'') denoted as , disjunction (''or'') denoted as , and negation (''not'') denoted as . Elementary algebra, on the other hand, uses arithmetic operators such as addition, multiplication, subtraction, and division. Boolean algebra is therefore a formal way of describing logical operations in the same way that elementary algebra describes numerical operations. Boolean algebra was introduced by George Boole in his first book ''The Mathematical Analysis of Logic'' (1847), and set forth more fully in his ''An Investigation of the Laws of Thought'' (1854). According to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Storage Device
Data ( , ) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted formally. A datum is an individual value in a collection of data. Data are usually organized into structures such as tables that provide additional context and meaning, and may themselves be used as data in larger structures. Data may be used as variables in a computational process. Data may represent abstract ideas or concrete measurements. Data are commonly used in scientific research, economics, and virtually every other form of human organizational activity. Examples of data sets include price indices (such as the consumer price index), unemployment rates, literacy rates, and census data. In this context, data represent the raw facts and figures from which useful information can be extracted. Data are collected using techniques ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punched Tape
file:PaperTapes-5and8Hole.jpg, Five- and eight-hole wide punched paper tape file:Harwell-dekatron-witch-10.jpg, Paper tape reader on the Harwell computer with a small piece of five-hole tape connected in a circle – creating a physical program loop Punched tape or perforated paper tape is a form of data storage that consists of a long strip of paper through which small holes are punched. It was developed from and was subsequently used alongside punched cards, the difference being that the tape is continuous. Punched cards, and chains of punched cards, were used for control of looms in the 18th century. Use for telegraphy systems started in 1842. Punched tapes were used throughout the 19th and for much of the 20th centuries for programmable looms, teleprinter communication, for input to computers of the 1950s and 1960s, and later as a storage medium for minicomputers and Numerical control, CNC machine tools. During the Second World War, high-speed punched tape systems using opti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Monitor
A computer monitor is an output device that displays information in pictorial or textual form. A discrete monitor comprises a electronic visual display, visual display, support electronics, power supply, Housing (engineering), housing, electrical connectors, and external user controls. The display in modern monitors is typically an Liquid-crystal display, LCD with LED-backlit LCD, LED backlight, having by the 2010s replaced cold-cathode fluorescent lamp, CCFL Backlight, backlit LCDs. Before the mid-2000s, most monitors used a cathode-ray tube, cathode-ray tube (CRT) as the image output technology. A monitor is typically connected to its host computer via DisplayPort, HDMI, USB-C, Digital Visual Interface, DVI, or VGA connector, VGA. Monitors sometimes use other proprietary connectors and signals to connect to a computer, which is less common. Originally computer monitors were used for data processing while television sets were used for video. From the 1980s onward, computers ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronics
Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other Electric charge, electrically charged particles. It is a subfield of physics and electrical engineering which uses Passivity (engineering), active devices such as transistors, diodes, and integrated circuits to control and amplify the flow of electric current and to convert it from one form to another, such as from alternating current (AC) to direct current (DC) or from analog signal, analog signals to digital signal, digital signals. Electronic devices have significantly influenced the development of many aspects of modern society, such as telecommunications, entertainment, education, health care, industry, and security. The main driving force behind the advancement of electronics is the semiconductor industry, which continually produces ever-more sophisticated electronic devices and circuits in respo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modem
The Democratic Movement (, ; MoDem ) is a centre to centre-right political party in France, whose main ideological trends are liberalism and Christian democracy, and that is characterised by a strong pro-Europeanist stance. MoDem was established by François Bayrou to succeed the Union for French Democracy (UDF) and contest the 2007 legislative election, after his strong showing in the 2007 presidential election. Initially named the Democratic Party (''Parti démocrate''), the party was renamed "Democratic Movement", because there was already a small Democratic Party in France. MoDem secured an agreement with La République En Marche! (LRM) — later Renaissance (RE) — in the 2017 legislative election after Bayrou had endorsed the candidacy of Emmanuel Macron in February. The two parties have since been in alliance, as of late named Ensemble. The party's founder and leader Bayrou has served as Prime Minister of France since December 2024. History Background MoDem tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency-shift Keying
Frequency-shift keying (FSK) is a frequency modulation scheme in which digital information is encoded on a carrier signal by periodically shifting the frequency of the carrier between several discrete frequencies. The technology is used for communication systems such as telemetry, weather balloon radiosondes, caller ID, garage door openers, and low frequency radio transmission in the VLF and ELF bands. The simplest FSK is binary FSK (BFSK, which is also commonly referred to as 2FSK or 2-FSK), in which the carrier is shifted between two discrete frequencies to transmit binary (0s and 1s) information. Modulating and demodulating Reference implementations of FSK modems exist and are documented in detail. The demodulation of a binary FSK signal can be done using the Goertzel algorithm very efficiently, even on low-power microcontrollers. Variations Multiple frequency-shift keying Continuous-phase frequency-shift keying In principle FSK can be implemented by usin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Detroit
Detroit ( , ) is the List of municipalities in Michigan, most populous city in the U.S. state of Michigan. It is situated on the bank of the Detroit River across from Windsor, Ontario. It had a population of 639,111 at the 2020 United States census, 2020 census, making it the List of United States cities by population, 26th-most populous city in the United States and the largest U.S. city on the Canada–United States border. The Metro Detroit area, home to 4.3 million people, is the second-largest in the Midwestern United States, Midwest after the Chicago metropolitan area and the 14th-largest in the United States. The county seat, seat of Wayne County, Michigan, Wayne County, Detroit is a significant cultural center known for its contributions to music, art, architecture and design, in addition to its historical automotive and industrial background. In 1701, Kingdom of France, Royal French explorers Antoine de la Mothe Cadillac and Alphonse de Tonty founded Fort Pontc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
