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Amateur Radio History
The history of amateur radio, dates from the dawn of radio communications, with published instructions for building simple wireless sets appearing at the beginning of the twentieth century. Throughout its history, amateur radio enthusiasts have made significant contributions to science, engineering, industry, and social services. Research by amateur radio operators has founded new industries, built economies, empowered nations, and saved lives in times of emergency. Beginnings Amateur radio came into being after radio waves (proved to exist by Heinrich Rudolf Hertz in 1888) were adapted into a communication system in the 1890s by the Italian inventor Guglielmo Marconi. In the late 19th century there had been amateur ''wired'' telegraphers setting up their own interconnected telegraphic systems. Following Marconi's success many people began experimenting with this new form of "wireless telegraphy". Information on "Hertzian wave" based wireless telegraphy systems (the name "radio" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communications. The term "amateur" is used to specify "a duly authorised person interested in radioelectric practice with a purely personal aim and without pecuniary interest;" (either direct monetary or other similar reward) and to differentiate it from commercial broadcasting, public safety (such as police and fire), or professional two-way radio services (such as maritime, aviation, taxis, etc.). The amateur radio service (''amateur service'' and ''amateur-satellite service'') is established by the International Telecommunication Union (ITU) through the Radio Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual station licenses with a unique identifying call sign, which m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NRAO
The National Radio Astronomy Observatory (NRAO) is a federally funded research and development center of the United States National Science Foundation operated under cooperative agreement by Associated Universities, Inc. for the purpose of radio astronomy. NRAO designs, builds, and operates its own high-sensitivity radio telescopes for use by scientists around the world. Locations Charlottesville, Virginia The NRAO headquarters is located on the campus of the University of Virginia in Charlottesville, Virginia. The North American ALMA Science Center and the NRAO Technology Center and Central Development Laboratory are also in Charlottesville. Green Bank, West Virginia NRAO was, until October 2016, the operator of the world's largest fully steerable radio telescope, the Robert C. Byrd Green Bank Telescope, which stands near Green Bank, West Virginia. The observatory contains several other telescopes, among them the telescope that utilizes an equatorial mount uncommon for radio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West Hartford, Connecticut
West Hartford is a town in Hartford County, Connecticut, United States, west of downtown Hartford. The population was 64,083 at the 2020 census. The town's popular downtown area is colloquially known as "West Hartford Center," or simply "The Center," and is centered on Farmington Avenue and South/North Main Street. West Hartford Center has been the community's main hub since the late 17th century. Incorporated as a town in 1854, West Hartford was previously a parish of Hartford, founded in 1672. Among the southernmost of the communities in the Hartford-Springfield Knowledge Corridor metropolitan region, West Hartford is home to University of Hartford and the University of Saint Joseph. West Hartford is home to regular events which draw large crowds from neighboring towns, including the Elizabeth Park Concert Series. The town also hosts the annual Celebrate West Hartford event, which includes fairground rides, food vendors, and stalls by local businesses. History Accordi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
London
London is the capital and List of urban areas in the United Kingdom, largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a major settlement for two millennia. The City of London, its ancient core and financial centre, was founded by the Roman Empire, Romans as ''Londinium'' and retains its medieval boundaries.See also: Independent city#National capitals, Independent city § National capitals The City of Westminster, to the west of the City of London, has for centuries hosted the national Government of the United Kingdom, government and Parliament of the United Kingdom, parliament. Since the 19th century, the name "London" has also referred to the metropolis around this core, historically split between the Counties of England, counties of Middlesex, Essex, Surrey, Kent, and Hertfordshire, which largely comprises Greater London ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area extends from the Rhine to the Atlantic Ocean and from the Mediterranean Sea to the English Channel and the North Sea; overseas territories include French Guiana in South America, Saint Pierre and Miquelon in the North Atlantic, the French West Indies, and many islands in Oceania and the Indian Ocean. Due to its several coastal territories, France has the largest exclusive economic zone in the world. France borders Belgium, Luxembourg, Germany, Switzerland, Monaco, Italy, Andorra, and Spain in continental Europe, as well as the Netherlands, Suriname, and Brazil in the Americas via its overseas territories in French Guiana and Saint Martin. Its eighteen integral regions (five of which are overseas) span a combined area of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five major unincorporated territories, nine United States Minor Outlying Islands, Minor Outlying Islands, and 326 Indian reservations. The United States is also in Compact of Free Association, free association with three Oceania, Pacific Island Sovereign state, sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Palau, Republic of Palau. It is the world's List of countries and dependencies by area, third-largest country by both land and total area. It shares land borders Canada–United States border, with Canada to its north and Mexico–United States border, with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the List of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bundesarchiv Bild 102-10989, Sanitäter Auf Skiern Mit Sendestation
, type = Archive , seal = , seal_size = , seal_caption = , seal_alt = , logo = Bundesarchiv-Logo.svg , logo_size = , logo_caption = , logo_alt = , image = Bundesarchiv Koblenz.jpg , image_caption = The Federal Archives in Koblenz , image_alt = , formed = , preceding1 = , preceding2 = , dissolved = , superseding1 = , superseding2 = , agency_type = , jurisdiction = , status = Active , headquarters = PotsdamerStraße156075Koblenz , coordinates = , motto = , employees = , budget = million () , chief1_name = Michael Hollmann , chief1_position = President of the Federal Archives , chief2_name = Dr. Andrea Hänger , chief2_position ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
One KW Ham Station
1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit of counting or measurement. For example, a line segment of ''unit length'' is a line segment of length 1. In conventions of sign where zero is considered neither positive nor negative, 1 is the first and smallest positive integer. It is also sometimes considered the first of the infinite sequence of natural numbers, followed by 2, although by other definitions 1 is the second natural number, following 0. The fundamental mathematical property of 1 is to be a multiplicative identity, meaning that any number multiplied by 1 equals the same number. Most if not all properties of 1 can be deduced from this. In advanced mathematics, a multiplicative identity is often denoted 1, even if it is not a number. 1 is by convention not considered a prime number; this was not universally accepted until the mid-20th century. Additionally, 1 is the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fighting occurring throughout Europe, the Middle East, Africa, the Pacific Ocean, Pacific, and parts of Asia. An estimated 9 million soldiers were killed in combat, plus another 23 million wounded, while 5 million civilians died as a result of military action, hunger, and disease. Millions more died in Genocides in history (World War I through World War II), genocides within the Ottoman Empire and in the Spanish flu, 1918 influenza pandemic, which was exacerbated by the movement of combatants during the war. Prior to 1914, the European great powers were divided between the Triple Entente (comprising French Third Republic, France, Russia, and British Empire, Britain) and the Triple A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etymology Of Ham Radio
''Ham radio'' is a popular term for amateur radio, derived from "ham" as an informal name for an amateur radio operator. The use first appeared in the United States during the opening decade of the 20th century—for example, in 1909, Robert A. Morton reported overhearing an amateur radio transmission which included the comment: "Say, do you know the fellow who is putting up a new station out your way? I think he is a ham." However, the term did not gain widespread usage in the United States until around 1920, after which it slowly spread to other English-speaking countries. Etymology At the turn of the 20th century, the terms "ham" and "plug" were used by landline telegraphers to describe an operator "who lacks ability" or who had poor or "ham fisted" skills. By 1881, it had been alleged by telegrapher unions and trade groups that companies were employing "ham" operators who were negligent or incompetent. These unskilled operators were described as either drinking alcohol w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Convention For The Safety Of Life At Sea
The International Convention for the Safety of Life at Sea (SOLAS) is an international maritime treaty that sets minimum safety standards in the construction, equipment and operation of merchant ships. The International Maritime Organization convention requires signatory flag states to ensure that ships flagged by them comply with at least these standards. The current version of SOLAS is the 1974 version, known as SOLAS 1974, which came into force on 25 May 1980. , SOLAS 1974 has 167 contracting states, which flag about 99% of merchant ships around the world in terms of gross tonnage. SOLAS in its successive forms is generally regarded as the most important of all international treaties concerning the safety of merchant ships. Signatories The non-parties to SOLAS 1974 include numerous landlocked countries (for obvious reasons), as well as El Salvador, Micronesia and East Timor. Some others including Bolivia, Lebanon and Sri Lanka, all considered flag of convenience state ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
