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| isbn = 0313398631
}}</ref> durante las décadas de 1960 y 1970. Su reducido tamaño disparó un cambio en los hábitos de las personas al permitirles escuchar música y noticias donde quiera que fueran. A partir de comienzos de la década de 198 las radios a transistores [[Amplitud modulada|AM]] fueron superadas por dispositivos con mejor calidad de audio, reproductores portátiles de CDs y reproductores personales de audio.
==Antecedentes==
[[ImageArchivo:Pocket radio open english.jpg|thumb|Radio con cinco transistores, con su parte posterior abierta mostrando sus partes.]]
Antes que se inventara el transistor, las radios usedutilizaban [[vacuum tubeválvula]]s. AlthoughAunque portablese vacuum tubefabricaron radios wereportátiles produceda válvulas, theylas weremismas bulkyeran andvoluminosas heavyy duepesadas toa thecausa largede batterieslas andgrandes [[transformer]]sbaterías y transformadores necesarios requiredpara byalimentar theel highgran powerconsumo consumptionde ofpotencia thede vacuumlas tubesválvulas.
El 23 de diciembre de 1947 en los [[Bell Laboratories]] demonstratedse thehizo firstfuncionar el primer [[transistor]] on December 23, 1947.<ref>[http://www.juliantrubin.com/bigten/transistorexperiments.html The Invention of the Transistor]</ref> TheEl scientificequipo teamde atcientíficos Bellque Laboratoriesdesarrolló responsibleel foramplificador thede [[solid-stateestado sólido physics|solid-state]]en los Bell Laboratories estaba amplifierformado includedpor [[William Shockley]], [[Walter Houser Brattain]], andy [[John Bardeen]].<ref>{{cite book | title = Made In Japan : Transistor Radios of the 1950s and 1960s | author = Handy, Erbe, Blackham, Antonier | publisher = Chronicle Books | year = 1993 | isbn = 0-8118-0271-X}} page 13</ref> AfterLuego obtainingde patentobtener protectionuna patente por el invento, thela companyempresa heldbrindo auna newsconferencia conferencede onprensa Juneel 30, de junio de 1948, aten whichla acual prototypese transistorpresentó un prototipo de una radio wasa demonstratedtransistores.<ref name="The Revolution in Your Pocket">{{Cite web|url=http://www.americanheritage.com/articles/magazine/it/2004/2/2004_2_12.shtml|title=The Revolution in Your Pocket|accessdate=2010-04-20}}</ref>
There are many claimants to the title of the first company to produce practical transistor radios, often incorrectly attributed to [[Sony]] (originallyoriginalmente Tokyo Telecommunications Engineering Corporation). [[Texas Instruments]] had demonstrated all-transistor AM (amplitude modulation) radios as early as May 25, 1954,<ref>Invention and Technology Magazine, Fall 2004, Volume 20 Issue 2, "The Revolution in your Pocket", Author: Robert J. Simcoe</ref><ref>Book Title: TI, the Transistor, and Me, Author: Ed Millis, page 34</ref> but their performance was well below that of equivalent vacuum tube models. A workable all-transistor radio was demonstrated in August 1953 at the [[Düsseldorf]] Radio Fair by the German firm Intermetall.<ref>Article: "The French Transistor", Author: Armand Van Dormael, page 15, Source: IEEE Global History Network</ref> It was built with four of [[Intermetall]]'s hand-made transistors, based upon the 1948 invention of the "Transistron"-germanium point-contact transistor by [[Herbert Mataré]] and [[Heinrich Welker]]. However, as with the early Texas Instruments units (and others) only prototypes were ever built; it was never put into commercial production. RCA had demonstrated a prototype transistor radio as early as 1952 and it is likely that they and the other radio makers were planning transistor radios of their own, but Texas Instruments and Regency Division of I.D.E.A., were the first to offer a production model starting in October 1954.<ref>website: www.regencytr1.com, Regency TR-1 Transistor Radio History</ref>
[[Image:Sanyo Transistor.jpg|thumb|left|200|[[Sanyo]] 8S-P3 transistor radio, which received AM and shortwave bands.]]
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