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Edmond Bruce
Edmond Bruce (September 28, 1899 – November 28, 1973) was an American radio pioneer best known for creating the rhombic antenna and Bruce array. Bruce was born in Saint Louis, Missouri, and raised in Cambridge, Massachusetts, Brooklyn, and Washington, D.C. In 1917 he left high school to join the Navy and was eventually chief radio electrician in the transatlantic communication service, serving at the Otter Cliffs Radio Station in Bar Harbor, Maine. He then studied at George Washington University, 1919, and at Massachusetts Institute of Technology, 1920–1924, from which he received his bachelor's degree in electrical communication. From 1921 to 1923 he also worked for Melville Eastham's Clapp-Eastham Company. In 1924 he joined the Western Electric Company, and in 1925 became a research engineer at Bell Telephone Laboratories, where he helped develop short-wave radio receivers and field strength measuring equipment, and designed directional antennas for short-wave radio commu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Missouri
Missouri (''see #Etymology and pronunciation, pronunciation'') is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it borders Iowa to the north, Illinois, Kentucky and Tennessee to the east, Arkansas to the south and Oklahoma, Kansas, and Nebraska to the west. In the south are the Ozarks, a forested highland, providing timber, minerals, and recreation. At 1.5 billion years old, the St. Francois Mountains are among the oldest in the world. The Missouri River, after which the state is named, flows through the center and into the Mississippi River, which makes up the eastern border. With over six million residents, it is the List of U.S. states and territories by population, 19th-most populous state of the country. The largest urban areas are St. Louis, Kansas City, Missouri, Kansas City, Springfield, Missouri, Springfield, and Columbia, Missouri, Columbia. The Cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otter Cliffs Radio Station
U.S. Naval Radio Station Otter Cliffs was a United States Navy radio receiver facility located in Acadia National Park on Mount Desert Island, south of Bar Harbor, Maine. The station was commissioned on August 28, 1917, under the command of Lt. Alessandro Fabbri, who had personally cleared the land, built and equipped the station, and offered it to the government in exchange for a commission in the Naval Reserve and assignment as Officer-in-Charge. Prior to the war, Fabbri was a licensed radio amateur with the U.S. Government issued call sign 1AJ. Otter Cliffs was the Navy's best transatlantic radio receiver site because of its absence of nearby man-made radio noise, its unobstructed ocean path from Europe, and the outstanding receivers, antennas and noise mitigation techniques developed by the Wireless Specialty Apparatus Company under the leadership of Greenleaf Whittier Pickard. Pickard is well known for his early inventions in connection with loop aerials, direction-finding s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AC75
The AC75 (America's Cup 75) is a racing yacht used in the 2021 America's Cup and 37th America's Cup matches and planned to be used for the 38th America's Cup match. The monohulls feature wing-like sailing hydrofoils mounted under the hull, a soft wingsail, and no keel. The rule Following the 2017 America's Cup, winners Royal New Zealand Yacht Squadron accepted a notice of challenge from Circolo della Vela Sicilia stipulating a monohull would be used in 2021. Conceptual graphics of a monohull with soft sails and topside canting hydrofoils were released on 21 November 2017, and the first draft of the class rule was published by the defender and the challenger of record on 29 March 2018. The return to monohulls with soft sails after three America's Cups on multihulls with wingsails is reminiscent of earlier America's Cup classes and seaworthy traditions, but the rule included hydrofoils to attract high performance crews and large TV audiences. Under the protocol, each competin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sailing Hydrofoil
A sailing hydrofoil, hydrofoil sailboat, or hydrosail is a sailboat with wing-like hydrofoil, foils mounted under the hull (watercraft), hull. As the craft increases its speed the hydrofoils Lift (force), lift the hull up and out of the water, greatly reducing wetted area, resulting in decreased Drag (physics), drag and increased speed. A sailing hydrofoil can achieve speeds exceeding double and in some cases triple the wind speed. Both monohull and multihull sailboats can be retrofitted with hydrofoils, although greater stability can be achieved by using the wider planform of a catamaran or trimaran. Typical configurations Some multihulls use three foils; two main forward foils provide lift so that the boat "flies" while a horizontal foil on the rudder is trimmed to drive and control altitude. On catamarans, a single main foil can be attached between the hulls just in front of the center of gravity and at 2 degrees of incidence, spanning the tunnel with supporting struts. Hydrof ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franklin Institute
The Franklin Institute is a science museum and a center of science education and research in Philadelphia, Pennsylvania. It is named after the American scientist and wikt:statesman, statesman Benjamin Franklin. It houses the Benjamin Franklin National Memorial. Founded in 1824, the Franklin Institute is one of the oldest centers of science education and development in the United States. Its chief astronomer is Derrick Pitts. History 19th century On February 5, 1824, Samuel Vaughan Merrick and William H. Keating founded the Franklin Institute of the State of Pennsylvania for the Promotion of the Artes Mechanicae, Mechanic Arts. The opening was chronicled by ''The Literary Chronicle for the Year 1824'': Begun in 1825, the institute was an important force in the professionalization of American science and technology through the nineteenth century, beginning with early investigations into steam engines and water power. In addition to conducting scientific inquiry, it fostered re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Astronomy
Radio astronomy is a subfield of astronomy that studies Astronomical object, celestial objects using radio waves. It started in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation coming from the Milky Way. Subsequent observations have identified a number of different sources of radio emission. These include stars and galaxy, galaxies, as well as entirely new classes of objects, such as Radio galaxy, radio galaxies, quasars, pulsars, and Astrophysical maser, masers. The discovery of the cosmic microwave background radiation, regarded as evidence for the Big Bang, Big Bang theory, was made through radio astronomy. Radio astronomy is conducted using large Antenna (radio), radio antennas referred to as ''radio telescopes'', that are either used alone, or with multiple linked telescopes utilizing the techniques of Astronomical interferometer, radio interferometry and aperture synthesis. The use of interferometry allows radio astronomy to achieve high angular resolu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Jansky
Karl Guthe Jansky (October 22, 1905 – February 14, 1950) was an American physicist and radio engineer who in April 1933 first announced his discovery of radio waves emanating from the Milky Way in the constellation Sagittarius. He is considered one of the founding figures of radio astronomy. Early life Karl Guthe Jansky was born 1905 in what was then the Territory of Oklahoma where his father, Cyril M. Jansky, was dean of the college of engineering at the University of Oklahoma at Norman. Cyril M. Jansky, born in Wisconsin of Czech immigrants, had started teaching at the age of sixteen. He was a teacher throughout his active life, retiring as professor of electrical engineering at the University of Wisconsin. He was an engineer with a strong interest in physics, a trait passed on to his sons. Karl Jansky was named after Dr. Karl Eugen Guthe, a professor of physics at the University of Michigan who had been an important mentor to Cyril M. Jansky. Karl Jansky's mother, bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directional Antenna
A directional antenna or beam antenna is an antenna that radiates or receives greater radio wave power in specific directions. Directional antennas can radiate radio waves in beams, when greater concentration of radiation in a certain direction is desired, or in receiving antennas receive radio waves from one specific direction only. This can increase the power transmitted to receivers in that direction, or reduce interference from unwanted sources. This contrasts with omnidirectional antennas such as dipole antennas which radiate radio waves over a wide angle, or receive from a wide angle. The extent to which an antenna's angular distribution of radiated power, its radiation pattern, is concentrated in one direction is measured by a parameter called antenna gain. A high-gain antenna (HGA) is a directional antenna with a focused, narrow beam width, permitting more precise targeting of the radio signals. Most commonly referred to during space missions, these antennas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Short-wave Radio
Shortwave radio is radio transmission using radio frequencies in the shortwave bands (SW). There is no official definition of the band range, but it always includes all of the high frequency band (HF), which extends from 3 to 30 MHz (approximately 100 to 10 metres in wavelength). It lies between the medium frequency band (MF) and the bottom of the VHF band. Radio waves in the shortwave band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere. Therefore, short waves directed at an angle into the sky can be reflected back to Earth at great distances, beyond the horizon. This is called skywave or "skip" propagation. Thus shortwave radio can be used for communication over very long distances, in contrast to radio waves of higher frequency, which travel in straight lines (line-of-sight propagation) and are generally limited by the visual horizon, about 64 km (40 miles). Shortwave broadcasts of radio pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell Telephone Laboratories
Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the company operates several laboratories in the United States and around the world. As a former subsidiary of the American Telephone and Telegraph Company (AT&T), Bell Labs and its researchers have been credited with the development of radio astronomy, the transistor, the laser, the photovoltaic cell, the charge-coupled device (CCD), information theory, the Unix operating system, and the programming languages B (programming language), B, C (programming language), C, C++, S (programming language), S, SNOBOL, AWK, AMPL, and others, throughout the 20th century. Eleven Nobel Prizes and five Turing Awards have been awarded for work completed at Bell Laboratories. Bell Labs had its origin in the complex corporate organization of the Bell System telepho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Electric Company
Western Electric Co., Inc. was an American electrical engineering and manufacturing company that operated from 1869 to 1996. A subsidiary of the AT&T Corporation for most of its lifespan, Western Electric was the primary manufacturer, supplier, and purchasing agent for all telephone equipment for the Bell System from 1881 until 1984, when Breakup of the Bell System, the Bell System was dismantled. Because the Bell System had a near-total monopoly over telephone service in the United States for much of the 20th century, Western Electric's equipment was widespread across the country. The company was responsible for many technological innovations, as well as developments in industrial management. History 19th century In 1856, George Shawk, a craftsman and telegraph maker, purchased an electrical engineering business in Cleveland, Ohio. In January 1869, Shawk had partnered with Enos M. Barton in the former Western Union repair shop of Cleveland, to manufacture burglar alarms, fire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
