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==Sajarah==
{{details|Sajarah radio}}
[[Image:TeslaWirelessPower1891.png|thumb|333px|right|Tesla demonstratingkeur wirelessmintonkeun transmissionspangiriman duringinformasi hisnirkabel highdina frequencykuliah andngeunaan potentialfrékuénsi lectureluhur ofdina taun 1891. AfterSaenggeus continuedngalakukeun researchrisét anu sinambung, Tesla gavengajelaskeun thedasar-dasar fundamentals ofngeunaan radio indina taun 1893.]]
InDina taun 1893, indi [[St. Louis, Missouri|St. Louis]], [[Missouri]], [[Nikola Tesla]] madenyieun devicesalat forpikeun his experiments withpercobaan [[electricitylistrik]]. AddressingBiantara thedi hareupeun ''[[Franklin Institute]]'' indi [[Philadelphia]] and thesarta ''[[National Electric Light Association]]'', hemanéhna described and demonstrated in detail the principles of his wireless work. [http://www.ieee-virtual-museum.org/collection/people.php?taid=&id=1234597&lid=1] The descriptions contained all the elements that were later incorporated into radio systems before the development of the [[vacuum tube]]. He initially experimented with magnetic receiversngajelaskeun, unlikemintonkeun thesarta [[coherer]]sngawincik (detecting devices consisting of tubes filled with [[iron]] filings which had been invented by [[Temistocle Calzecchiprinsip-Onesti]]prinsip atgawé Fermo in Italy in 1884) used by [[Guglielmo Marconi]] and other early experimenters. [http://www.teslasociety.com/teslarec.pdf]nirkabelna.
InDina taun [[1894]] [[Alexander Stepanovich Popov]] built his firstnyieun [[radio receiver]], whichanu containedngandung ahiji [[coherer]]. FurtherSatuluyna refinedmanéhna asnyampurnakeun aéta alat jadi hiji [[lightningdetektor detectorcahaya]], itanu wasdibébérkeun presented to thehareupeun [[Russian Physical and Chemical Society]] ondina tanggal [[May 7]], [[1895]].
ThePintonan firsttelegrafi publicnirkabel demonstrationmunggaran ofhareupeun wirelessbalaréa telegraphylumangsung tookdi placeruang inkuliah the lecture theatreMuseum ofSajarah theAlam Oxford University Museumdina oftanggal Natural14 History on August 14,Agustus 1894, carriedanu outdilaksanakeun byku ProfessorProfésor [[Oliver Lodge]] andjeung [[Alexander Muirhead]]. DuringDina theéta demonstrationpintonan, ahiji sinyal radio signaldikirim wasti sentgedong from the neighbouringlaboratorium Clarendon, laboratorysarta building,ditarima andku receivedalat byanu apparatusditempatkeun indi theruang lecturekuliah theatredimaksud.
InDina taun [[1896]], Marconi wasdibéré awarded[[patent]] the12039 ku [[United Kingdom|BritishInggris]] [[patent]] 12039, ''Improvements in transmitting electrical impulses and signals and in apparatus there-for'',. forDina radio. Intaun 1897 hemanéhna establishedngadegkeun thestasiun world'sradio first radiomunggaran stationdi ondunya thedi [[Isle of Wight]], [[EnglandInggris]]. Marconi openedmuka the world's firstpabrik "wirelessnirkabel" factorymunggaran indi dunya di Hall Street, [[Chelmsford, EnglandInggris]] indina taun 1898, employinganu aroundngagawékeun kira-kira 50 peopleurang.
TheTitimuan nexthébat greatsatuluyna inventionnyaéta was thedetéktor [[vacuumbungbung tubehapa]] detector, inventedanu katimu ku para byinsinyur [[Westinghouse Electric Corporation|Westinghouse]] engineers. OnDina [[Christmastanggal Eve]],25 Désémber 1906, [[Reginald Fessenden]] used angagunakeun ''synchronous rotary-spark transmitter'' forpikeun the first radiosiaran program broadcastradiona munggaran, fromti [[Ocean Bluff-Brant Rock, Massachusetts|Brant Rock, Massachusetts]]. Ships at sea heardKapal-kapal adi broadcastlaut thatngadéngé includedsiaran Fessenden playinganu ''[[O Holy Night]]'' on thengamaénkeun [[violin]] and reading a passage from the [[Biblebiola]]. Program Thewarta firstberita radio newsmunggaran programdisiarkeun was broadcastdina [[August 31 Agustus]], [[1920]] byku stationstasiun 8MK indi [[Detroit, Michigan]]. TheStasiun firstradio collegekampus radiomunggaran stationmitembeyan begansiaran broadcastingdina ontanggal [[October 14 Oktober]], 1920, fromti [[Union College]], [[Schenectady]], [[New York]] under the personal call letters of Wendell King, an African-American student at the school.[http://w2uc.union.edu/RADIO_web.htm] That month 2ADD, later renamed [[WRUC]] in 1940, aired what is believed to be the first public entertainment broadcast in the United States, a series of Thursday night concerts initially heard within a 100 mile radius and later for a 1,000 mile radius. In November 1920, it aired the first broadcast of a sporting event.[http://w2uc.union.edu/RADIO_web.htm],[http://2000.union.edu/N/DS/edition_display.php?e=677&s=2700] At 9 pm on August 27, 1920, Sociedad Radio Argentina aired a live performance of Richard Wagner's Parsifal opera from the Coliseo Theater in downtown Buenos Aires, only about twenty homes in the city had a receiver to tune in. Meanwhile, Regular entertainment broadcasts commenced in 1922 from the [[Guglielmo Marconi|Marconi]] Research Centre at [[Writtle]], near [[Chelmsford, England]].
One of the first developments in the early 20th century (1900-1959) was that [[aircraft]] used commercial AM radio stations for navigation. This continued until the early 1960s when [[VHF omnidirectional range|VOR]] systems finally became widespread (though AM stations are still marked on U.S. [[aviation]] charts). In the early 1930s, [[single sideband]] and [[frequency modulation]] were invented by amateur radio operators. By the end of the decade, they were established commercial modes. Radio was used to transmit pictures visible as [[television]] as early as the 1920s. Commercial television transmissions started in North America and Europe in the 1940s. In 1954, Regency introduced a pocket [[transistor]] radio, the [[Regency TR-1|TR-1]], powered by a "standard 22.5 V Battery".
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