Transistor radio

:"This article is about an electronic device. For the fourth studio album by M. Ward, see Transistor Radio.A transistor radio is a small transistor-based radio receiver. Historically, the term "transistor radio" refers to a radio that is monaural and typically receives only the 540–1600 kilocycle"Kilocycles" is an old term for what is today known as "kilohertz". The hertz was adopted as the new unit of frequency in 1960 (replacing the "cycle per second"), and became common use in the 1970s.] AM broadcast band.

History

There are numerous claimants to the title of the first company to produce practical transistor radios, often incorrectly attributed to Sony (originally Tokyo Tsushin Kogyo). Texas Instruments had demonstrated all-transistor AM (amplitude modulation) radios as early as 1952, but their performance was well below that of equivalent battery tube models. A workable all-transistor radio was demonstrated in August 1953 at the Düsseldorf Radio Fair by the German firm Intermetall. It was built with four of Intermetall's hand-made transistors, based upon the 1948 invention of Herbert Mataré and Heinrich Welker.However, as with the early Texas units (and others) only prototypes were ever built; it was never put into commercial production.

The Regency TR-1, announced on October 18, 1954 by the Regency Division of I.D.E.A (Industrial Development Engineering Associates of Indianapolis, Indiana) and put on sale in November 1954 was the first practical transistor radio made in any significant numbers. Patented by Dr. Heinz De Koster (Ph.D. of physics), a Dutch employee of the company. It cost $49.95 (the equivalent of roughly $364 in year-2006 dollars) and sold about 150,000 units. Raytheon and Zenith Electronics transistor radios soon followed and were priced even higher. Even the first Japanese imports (in 1957) were priced at $30 and above. Transistor radios did not achieve mass popularity until the early 1960s when prices of some models fell below $20, then below $10 as markets became flooded with radios from Hong Kong by the mid to late 1960s.

Texas Instruments was behind the Regency transistor radio. In May 1954, they had designed and built a prototype and were looking for an established radio manufacturer to develop and market a radio using their transistors. None of the major radio makers were interested. 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 were the first to put forth a production model. Sony, at the time still a small company named Tokyo Tsushin Kogyo, Ltd., (aka "Totsuko"), followed soon after introducing their own five-transistor radio, the TR-55, in August 1955, under the new brand name Sony [cite book | title = SONY : the private life | author = John Nathan | publisher = Houghton Mifflin Company | year = 1999 | isbn = 0-395-89327-5 page 35] . With its release, Sony also became the first company to manufacture a radio from the transistors on up, and to utilize all miniature components.

Sony's first official import to the U.S.A. was the "pocketable" [citeweb|url=http://www.sony.net/Fun/SH/1-6/h2.html|title=Sony Global - Sony History|accessdate=2008-09-01] TR-63 released in March 1957 [cite book | title = SONY : the private life | author = John Nathan | publisher = Houghton Mifflin Company | year = 1999 | isbn = 0-395-89327-5 page 35] , a model which proved highly successful in that market. (The term "pocketable" was a matter of some interpretation, as Sony allegedly had special shirts made with oversized pockets for their salesmen [citeweb|url=http://www.sony.net/Fun/SH/1-6/h2.html|title=Sony Global - Sony History|accessdate=2008-09-01] ). In January 1958, the company changed its name to Sony [cite book | title = SONY : the private life | author = John Nathan | publisher = Houghton Mifflin Company | year = 1999 | isbn = 0-395-89327-5 page 53] , adopting the name that had previously been the reserve of its radio brand. The Sony TR-610 was released some months later, marking another resounding success and taking its place as the first transistor radio to sell more than a half-million units.

The use of transistors instead of vacuum tubes as the amplifier elements meant that the device was much smaller and required far less power to operate than a tubed radio. It also ensured that reception was available instantly, since there were no filaments to heat up. The typical portable tube radio of the fifties was about the size and weight of a lunchbox, and contained several heavy (and non-rechargeable) batteries: one or more so-called "A" batteries just to heat the tube filaments and a large 45- to 90-volt "B" battery to power the signal circuits. By comparison, the "transistor" could fit in a pocket and weighed half a pound or less and was powered by standard flashlight batteries or a single compact 9-volt battery. (The now-familiar 9-volt battery was introduced specifically for powering transistor radios.)

Listeners sometimes held an entire transistor radio directly against the side of the head, with the speaker against the ear, to minimize the "tinny" sound caused by the high resonant frequency of its small speaker enclosure. Most radios included earphone jacks and came with single earphones that provided only middling-quality sound reproduction due to the bandwidth limitation of AM (up to 4500Hz). To consumers familiar with the earphone-listening experience of the transistor radio, the first Sony Walkman cassette player, with a pair of high-fidelity stereo earphones, would provide a greatly contrasting display of audio fidelity. The signal sensitivity of the radio depends on the amount of electric signal amplification. A good quality transistor radio could receive an AM signal from Edmonton in Calgary.

or chip. The prefix "transistor" basically now means an old pocket radio; it can be used to refer to any small radio, but the term itself is today somewhat obsolescent, since virtually all commercial broadcast receivers, pocket-sized or not, are now transistor-based.

Rise of digital audio player

Use of air signal only radios (AM/FM) have declined in popularity with the rise of portable digital audio players, which allow people to carry and listen to the music of their choosing and may also include a digital radio tuner. This is a popular choice with listeners who are dissatisfied with terrestrial music radio because of limited selection of music or other criticisms. However, transistor radios are still popular for news, weather, live sport events and emergency alert applications.

Their usage was kept widespread in third world nations, where electricity is erratic and extended battery life is paramount.

See also

*Broadcasting

References

Further reading

* Michael F. Wolff: "The secret six-month project. Why Texas Instruments decided to put the first transistor radio on the market by Christmas 1954 and how it was accomplished." IEEE Spectrum, December 1985, pages 64-69
*"Transistor Radios: 1954-1968" (Schiffer Book for Collectors) by Norman R. Smith
*"Made in Japan: Transistor Radios of the 1950s and 1960s" by Handy, Erbe, Blackham, Antonier (1993) (ISBN 0-8118-0271-X)
* [http://www.ericwrobbel.com/ Unique books on Transistor Radios] by Eric Wrobbel
*"The Portable Radio in American Life" by University of Arizona Professor Michael Brian Schiffer, Ph.D. (The University of Arizona Press, 1991).
*"Restoring Pocket Radios (DVD)" by Ron Mansfield and Eric Wrobbel. (ChildhoodRadios.com, 2002).
*"The Regency TR-1 story", based on an interview with Regency co-founder, John Pies (partner with Joe Weaver) [http://www.regencytr1.com/Regency_Early_Years.html/ www.regencytr1.com/Regency_Early_Years.html]

External links

*
* [http://www.ti.com/corp/docs/company/history/timeline/semicon/1950/docs/54regency.htm TI Information Bulletin] First Commercial Transistor Radio October 18, 1954
* [http://people.msoe.edu/~reyer/regency/ Website about the first transistor radio] by Dr. Steven Reyer, a Professor in the Electrical Engineering and Computer Science Department at the Milwaukee School of Engineering.
* [http://www.geocities.com/SoHo/Atrium/1031/trans/1trans.html M31 Galaxy of Transistor Radios] Transistor radio site with photos and info on classic transistor radios from the US, Japan, and Europe.
* [http://tabiwallah.com/radiowallah/ Radio Wallah] Historical data accompanied by hundreds of images covering early transistor radios.
* [http://www.ChildhoodRadios.com/ ChildhoodRadios.com] Website with restoration resources and community message board operated by Ron Mansfield
* [http://www.transistor.org/ Sarah's Transistor Radios] Extensive website displaying over 1500 transistor radios and other information.
* [http://www.regencytr1.com "Regency TR-1 Transistor Radio History": ] website with many historical references on the web and in published literature
* [http://people.msoe.edu/~reyer/regency/ "1954 to 2004, the TR-1's Golden Anniversary] ". In depth coverage of the Regency radio.
* [http://www.radioexpo.org Radio Expo] is the source for the latest historical information about the Regency TR-1 & Regency Electronics
* [http://www.geocities.com/aldoandr/transistor.html Geocities Transistor radio directory]
* [http://www.fiftiesradio.com Fifties-area Transistor radios]
* [http://www.transistorradiodesign.com/index.htm Transistor Radio Design] Focusing on the design and history of pocket transistor radios manufactured during the 1950s &1960's.
* [http://tenwatts.blogspot.com/search/label/transistor%20radio Arcane Radio Trivia] Transistor radio design article