Editing History of radio (section)

===Transistor technology===
[[File:Vintage Regency TR-1 4-Transistor Radio, Mandarin Red, Made in USA, Introduced In 1954 (8622359295).jpg|thumb|upright|The [[Regency TR-1]], which used [[Texas Instruments]]' [[NPN transistor]]s, was the world's first commercially produced [[transistor radio]] in 1954. Size: 3×5×1.25 inch (7.6×12.7×3.2 cm)]]

Following development of [[transistor]] technology, [[bipolar junction transistor]]s led to the development of the [[transistor radio]]. In 1954, the Regency company introduced a pocket transistor radio, the [[Regency TR-1|TR-1]], powered by a "standard 22.5 V Battery." In 1955, the newly formed [[Sony]] company introduced its first transistorized radio, the [[TR-55]].<ref name="pbs">{{cite web |url=https://www.pbs.org/transistor/background1/events/tradio.html |title=Transistor Radios |year=1999 |publisher=ScienCentral (pbs.org)|access-date=2018-02-03}}</ref> It was small enough to fit in a [[Waistcoat|vest]] pocket, powered by a small battery. It was durable, because it had no vacuum tubes to burn out. In 1957, Sony introduced the TR-63, the first mass-produced transistor radio, leading to the mass-market penetration of transistor radios.<ref name="Skrabec">{{cite book|last1=Skrabec| first1=Quentin R. Jr. |url=https://books.google.com/books?id=2kc69qrid9oC&pg=PA195|title=The 100 Most Significant Events in American Business: An Encyclopedia|date=2012|publisher=ABC-CLIO|isbn=978-0313398636|pages=195–97}}</ref> Over the next 20 years, transistors replaced tubes almost completely except for high-power [[transmitter]]s.

By the mid-1960s, the [[Radio Corporation of America]] (RCA) were using [[metal–oxide–semiconductor field-effect transistor]]s (MOSFETs) in their consumer products, including [[FM radio]], television and [[amplifier]]s.<ref name="Harrison">{{cite book|last1=Harrison|first1=Linden T.|url=https://books.google.com/books?id=03JmxpE39N4C&pg=PA185|title=Current Sources and Voltage References: A Design Reference for Electronics Engineers|date=2005|publisher=Elsevier|isbn=978-0080455556|page=185}}</ref> [[Metal–oxide–semiconductor]] (MOS) [[large-scale integration]] (LSI) provided a practical and economic solution for radio technology, and was used in [[mobile radio]] systems by the early 1970s.<ref name="Zeidler">{{cite journal|last1=Zeidler|first1=G.|last2=Becker|first2=D.|date=1974|title=MOS LSI Custom Circuits Offer New Prospects for Communications Equipment Design|url=https://books.google.com/books?id=TihQAAAAYAAJ|journal=Electrical Communication|publisher=[[Western Electric Company]]|volume=49–50|pages=88–92|quote=In many fields of communications equipment design, MOS LSI custom built circuits provide the only practical and economic solution. (...) A complete list of all applications is beyond the scope of this paper since new MOS developments are constantly being initiated in the various technical areas. Typical examples of completed and present MOS developments are:<br />— crosspoints<br />— multiplexers<br />— modems<br />— mobile radios}}</ref>