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Valdemar Poulsen
Valdemar Poulsen (23 November 1869 – 23 July 1942) was a Danish engineer who developed a magnetic wire recorder called the telegraphone in 1898. He also made significant contributions to early radio technology, including the first continuous wave radio transmitter, the Poulsen arc, which was used for a majority of the earliest audio radio transmissions, before being supplanted by the development of vacuum-tube transmitters. Early life Poulsen was born on 23 November 1869 in Copenhagen. He was the son of the Supreme Court judge ''Denmark and the Danes'' by William J. Harvey and Christian Reppien, 1915, pages 233-239. Jonas Nicolai Johannes Poulsen and Rebekka Magdalene ( Bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denmark
Denmark is a Nordic countries, Nordic country in Northern Europe. It is the metropole and most populous constituent of the Kingdom of Denmark,, . also known as the Danish Realm, a constitutionally unitary state that includes the Autonomous administrative division, autonomous territories of the Faroe Islands and Greenland in the north Atlantic Ocean.* * * Metropolitan Denmark, also called "continental Denmark" or "Denmark proper", consists of the northern Jutland peninsula and an archipelago of 406 islands. It is the southernmost of the Scandinavian countries, lying southwest of Sweden, south of Norway, and north of Germany, with which it shares a short border. Denmark proper is situated between the North Sea to the west and the Baltic Sea to the east.The island of Bornholm is offset to the east of the rest of the country, in the Baltic Sea. The Kingdom of Denmark, including the Faroe Islands and Greenland, has roughly List of islands of Denmark, 1,400 islands greater than in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wire Recording
Wire recording, also known as magnetic wire recording, was the first magnetic recording technology, an analog type of audio storage. It recorded sound signals on a thin steel wire using varying levels of magnetization. The first crude magnetic recorder was invented in 1898 by Valdemar Poulsen. The first magnetic recorder to be made commercially available anywhere was the Telegraphone, manufactured by the American Telegraphone Company, Springfield, Massachusetts in 1903. The wire is pulled rapidly across a recording head which magnetizes each point along the wire in accordance with the intensity and polarity of the electrical audio signal being supplied to the recording head at that instant. By later drawing the wire across the same or a similar head while the head is not being supplied with an electrical signal, the varying magnetic field presented by the passing wire induces a similarly varying electric current in the head, recreating the original signal at a reduced leve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Tube
A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It takes the form of an evacuated tubular envelope of glass or sometimes metal containing electrodes connected to external connection pins. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental Electronics, electronic functions such as signal amplifier, amplification and current Rectifier, rectification. Non-thermionic types such as vacuum phototubes achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light and measurement of its intensity. In both types the electrons are accelerated from the cathode to the anode by the electric field in the tube. The first, and simplest, vacuum tube, the diode or Flem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arc Converter
The arc converter, sometimes called the arc transmitter, or Poulsen arc after Danish engineer Valdemar Poulsen who invented it in 1903, was a variety of spark transmitter used in early wireless telegraphy. The arc converter used an electric arc to convert direct current electricity into radio frequency alternating current. It was used as a radio transmitter from 1903 until the 1920s when it was replaced by vacuum tube transmitters. One of the first transmitters that could generate continuous sinusoidal waves, it was one of the first technologies used to transmit sound (amplitude modulation) by radio. It is on the list of IEEE Milestones as a historic achievement in electrical engineering. History Elihu Thomson discovered that a carbon arc shunted with a series tuned circuit would "sing". This "singing arc" was probably limited to audio frequencies. Bureau of Standards credits William Duddell with the shunt resonant circuit around 1900. The English engineer William Duddell di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone Newspaper
Telephone Newspapers, introduced in the 1890s, transmitted news and entertainment to subscribers over telephone lines. They were the first example of electronic broadcasting, although only a few were established, most commonly in European cities. These systems predated the development, in the 1920s, of radio broadcasting. They were eventually supplanted by radio stations, because radio signals could more easily cover much wider areas with higher quality audio, without incurring the costs of a telephone line infrastructure. History The introduction of the telephone in the mid-1870s included numerous demonstrations of its use for transmitting musical concerts over various distances. In one particularly advanced example, Clément Ader prepared a listening room at the 1881 Paris Electrical Exhibition, where attendees could listen to performances, in stereo, from the Paris Grand Opera. The concept also appeared in Edward Bellamy's influential 1888 utopian novel, '' Looking Backwa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franz Josef Of Austria
Franz Joseph I or Francis Joseph I ( ; ; 18 August 1830 – 21 November 1916) was Emperor of Austria, King of Hungary, and the ruler of the other states of the Habsburg monarchy from 1848 until his death in 1916. In the early part of his reign, his realms and territories were referred to as the Austrian Empire, but were reconstituted as the dual monarchy of Austria-Hungary in 1867. From 1 May 1850 to 24 August 1866, he was also president of the German Confederation. In December 1848, Franz Joseph's uncle Emperor Ferdinand I abdicated the throne at Olomouc, as part of Minister President Felix zu Schwarzenberg's plan to end the Hungarian Revolution of 1848. Franz Joseph then acceded to the throne. In 1854, he married his first cousin Duchess Elisabeth in Bavaria, with whom he had four children: Sophie, Gisela, Rudolf, and Marie Valerie. Largely considered to be a reactionary, Franz Joseph spent his early reign resisting constitutionalism in his domains. The Austrian Empire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paris
Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of cities in the European Union by population within city limits, fourth-most populous city in the European Union and the List of cities proper by population density, 30th most densely populated city in the world in 2022. Since the 17th century, Paris has been one of the world's major centres of finance, diplomacy, commerce, culture, Fashion capital, fashion, and gastronomy. Because of its leading role in the French art, arts and Science and technology in France, sciences and its early adoption of extensive street lighting, Paris became known as the City of Light in the 19th century. The City of Paris is the centre of the Île-de-France region, or Paris Region, with an official estimated population of 12,271,794 inhabitants in January 2023, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exposition Universelle (1900)
The Exposition Universelle of 1900 (), better known in English as the 1900 Paris Exposition, was a world's fair held in Paris, France, from 14 April to 12 November 1900, to celebrate the achievements of the past century and to accelerate development into the next. It was the sixth of ten major expositions held in the city between 1855 and 1937. It was held at the esplanade of Les Invalides, the Champ de Mars, the Trocadéro and at the banks of the Seine between them, with an additional section in the Bois de Vincennes, and it was visited by more than fifty million people. Many international congresses and other events were held within the framework of the exposition, including the 1900 Summer Olympics. Many technological innovations were displayed at the Fair, including the '' Grande Roue de Paris'' ferris wheel, the '' Rue de l'Avenir'' moving sidewalk, the first ever regular passenger trolleybus line, escalators, diesel engines, electric cars, dry cell batteries, electr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peder Oluf Pedersen
Peder Oluf Pedersen (19 June 1874 – 30 August 1941) was a Danish engineer and physicist. He is notable for his work on electrotechnology, his cooperation with Valdemar Poulsen on the developmental work on Wire recorders, which he called a telegraphone, the arc converter known as the Poulsen Arc Transmitter, and his work on electrical currents in the ionosphere. Pedersen became a professor of telegraphy, telephony and radio in 1912.Biography from the History Center retrieved 2011 Sept 28 He became principal of the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valdemar Poulsen And P
Waldemar, Valdemar, Valdimar, or Woldemar is an Old High German given name. It consists of the elements ''wald-'' "power", "brightness" and ''-mar'' "fame". The name is considered the equivalent of the Latvian name Valdemārs, the Estonian name Voldemar, and the Slavic names Vladimir, Volodymyr, Uladzimir or Włodzimierz. The Old Norse form ''Valdamarr'' (also ''Valdarr'') occurs in the Guðrúnarkviða II as the name of a king of the Danes. The Old Norse form is also used in Heimskringla, in the story of Harald Hardrada, as the name of a ruler of Holmgard (Veliky Novgorod).Alison Finlay (2004). ''Fagrskinna: A Catalogue of the Kings of Norway''. Brillp. 236 The ''Fagrskinna'' kings' sagas also have ''Valdamarr'', in reference to both Vladimir the Great and Vladimir Yaroslavovich. People with the name include: Royalty :''Ordered chronologically'' * Valdemar I of Denmark or Waldemar the Great (1131–1182), King of Denmark * Valdemar of Denmark (bishop) (1157/1158–1235 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Playback Head
''Tape Head'' is the seventh studio album by American rock band King's X King's X is an American Rock music, rock band formed in Springfield, Missouri, in 1979. They were first called the Edge and later became Sneak Preview before settling on its current name in 1985. The band's current lineup has remained intact fo ..., released in 1998 via Metal Blade Records. A music video was made for the song "Fade". "World" is a reworked song from the band's ''Sneak Preview'' demos. The controversial unreleased track "Quality Control" is included on the album, but has been re-titled to "Happy". The majority of the lyrics are now different, including the lack of profanity. The album cover picture is that of Doug Pinnick wrapped in recording tape. According to Pinnick, he brought the songs "Happy", "Cupid" and "Hate You", and Ty Tabor brought "Ocean" to the ''Tape Head'' recording sessions. All other songs were band created during the recording session. The song "Walter Bela Far ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
