Transistor radio
A transistor radio is a small portable radio receiver using transistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...

-based circuitry. Following their development in 1954 they became the most popular electronic communication device in history, with billions manufactured during the 1960s and 1970s. Their pocket size sparked a change in popular music listening habits, for the first time allowing people to listen to music anywhere they went. In the 1970s their popularity declined as other portable media players such as boom boxes and portable cassette players took over.


Bell Laboratories demonstrated the first transistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...

 on December 23, 1947. The scientific team at Bell Laboratories responsible for the solid-state
Solid-state physics
Solid-state physics is the study of rigid matter, or solids, through methods such as quantum mechanics, crystallography, electromagnetism, and metallurgy. It is the largest branch of condensed matter physics. Solid-state physics studies how the large-scale properties of solid materials result from...

 amplifier included William Shockley
William Shockley
William Bradford Shockley Jr. was an American physicist and inventor. Along with John Bardeen and Walter Houser Brattain, Shockley co-invented the transistor, for which all three were awarded the 1956 Nobel Prize in Physics.Shockley's attempts to commercialize a new transistor design in the 1950s...

, Walter Houser Brattain
Walter Houser Brattain
Walter Houser Brattain was an American physicist at Bell Labs who, along with John Bardeen and William Shockley, invented the transistor. They shared the 1956 Nobel Prize in Physics for their invention. He devoted much of his life to research on surface states.- Early life and education :He was...

, and John Bardeen
John Bardeen
John Bardeen was an American physicist and electrical engineer, the only person to have won the Nobel Prize in Physics twice: first in 1956 with William Shockley and Walter Brattain for the invention of the transistor; and again in 1972 with Leon Neil Cooper and John Robert Schrieffer for a...

. After obtaining patent protection, the company held a news conference on June 30, 1948, at which a prototype transistor radio was demonstrated. There are many claimants to the title of the first company to produce practical transistor radios, often incorrectly attributed to Sony
, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

 (originally Tokyo Tsushin Kogyo). Texas Instruments
Texas Instruments
Texas Instruments Inc. , widely known as TI, is an American company based in Dallas, Texas, United States, which develops and commercializes semiconductor and computer technology...

 had demonstrated all-transistor AM (amplitude modulation) radios as early as 1952, 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
Düsseldorf is the capital city of the German state of North Rhine-Westphalia and centre of the Rhine-Ruhr metropolitan region.Düsseldorf is an important international business and financial centre and renowned for its fashion and trade fairs. Located centrally within the European Megalopolis, the...

 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
Herbert Mataré
Herbert Franz Mataré was a German physicist. The focus of his research was the field of semiconductor research. His best-known work is the first functional "European" transistor, which he developed and patented together with Heinrich Welker in the vicinity of Paris in 1948, at the same time and...

 and Heinrich Welker
Heinrich Welker
Heinrich Johann Welker was a German theoretical and applied physicist who invented the "transistron", a form of transistor made at Westinghouse independently of the first successful transistor made at Bell Laboratories...

. 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 were the first to offer a production model.

The use of transistors instead of vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...

s as the amplifier elements meant that the device was much smaller, required far less power to operate than a tube radio, and was more shock-resistant. Transistors are current amplifiers, while tubes are voltage amplifiers. Since the transistor base draws current, its impedance
Impedance may refer to:*Electrical impedance, the ratio of the voltage phasor to the electric current phasor, a measure of the opposition to time-varying electric current in an electric circuit**Characteristic impedance of a transmission line...

 is low in contrast to the high impedance of the vacuum tubes. It also allowed "instant-on" operation, 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, non-rechargeable batteries — one or more so-called "A" batteries 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
PP3 battery
A nine-volt battery, the most common of which is designated a PP3 battery, is shaped as a rounded rectangular prism. 9-volt batteries are commonly used in pocket transistor radios, smoke detectors, carbon monoxide alarms, guitar effect units, and radio-controlled vehicle controllers...

 was introduced 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 mediocre-quality sound reproduction. 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 transistor radio remains the single most popular communications device in existence. Some estimates suggest that there are at least seven billion of them in existence, almost all tunable to the common AM band, and an increasingly high percentage of those also tunable to the FM band. Some receive shortwave
Shortwave radio refers to the upper MF and all of the HF portion of the radio spectrum, between 1,800–30,000 kHz. Shortwave radio received its name because the wavelengths in this band are shorter than 200 m which marked the original upper limit of the medium frequency band first used...

 broadcasts as well. Most operate on battery power. They have become small and cheap due to improved electronics which has the ability to pack millions of transistors on one integrated circuit
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

 or chip. To the general public, the prefix "transistor" means a pocket radio; it can be used to refer to any small radio, but the term itself is now obsolete, since virtually all commercial broadcast receivers, pocket-sized or not, are now transistor-based.

Regency TR-1 — the first transistor radio

Two companies working together, Texas Instruments of Dallas, Texas and Industrial Development Engineering Associates (I.D.E.A.) of Indianapolis, Indiana, were behind the unveiling of the Regency TR-1
Regency TR-1
The Regency TR-1 was the first commercially sold transistor radio.-History:Two companies working together, Texas Instruments of Dallas, Texas and Industrial Development Engineering Associates of Indianapolis, Indiana, were behind the unveiling of the Regency TR-1, the world's first...

, the world's first commercially produced transistor radio. Previously, Texas Instruments was producing instrumentation for the oil industry and locating devices for the U.S. Navy, and I.D.E.A. built home television antenna boosters, but the two companies worked together on the TR-1, looking to grow revenues for their respective companies by breaking into this new product area. In May 1954, Texas Instruments had designed and built a prototype and was looking for an established radio manufacturer to develop and market a radio using their transistors. None of the major radio makers including RCA, Philco, and Emerson were interested. The President of I.D.E.A. at the time, Ed Tudor, jumped at the opportunity to manufacture the TR-1, predicting sales of the transistor radios at "20 million radios in three years". The Regency TR-1 was announced on October 18, 1954 by the Regency Division of I.D.E.A., was put on sale in November 1954, and was the first practical transistor radio made in any significant numbers. Billboard
Billboard (magazine)
Billboard is a weekly American magazine devoted to the music industry, and is one of the oldest trade magazines in the world. It maintains several internationally recognized music charts that track the most popular songs and albums in various categories on a weekly basis...

reported in 1954 that "the radio has only four transistors. One acts a combination mixer-oscillator, one as an audio amplifier, and two as intermediate-frequency amplifiers." One year after the release of the TR-1 sales approached the 100,000 mark. The look and size of the TR-1 was well received, but the reviews of the TR-1's performance were typically adverse. The Regency TR-1 is patented by Richard C. Koch, , former Project Engineer of I.D.E.A.

Raytheon 8-TP-1 — the second transistor radio

In February 1955 the second transistor radio, the 8-TP-1, was introduced by Raytheon
Raytheon Company is a major American defense contractor and industrial corporation with core manufacturing concentrations in weapons and military and commercial electronics. It was previously involved in corporate and special-mission aircraft until early 2007...

. It was a larger portable transistor radio, including an expansive four-inch speaker and four additional transistors (the TR-1 used only four). As a result the sound quality was much better than the TR-1. An additional benefit of the 8-TP-1 was its efficient battery consumption. In July 1955, the first positive review of a transistor radio appeared in the Consumer Reports
Consumer Reports
Consumer Reports is an American magazine published monthly by Consumers Union since 1936. It publishes reviews and comparisons of consumer products and services based on reporting and results from its in-house testing laboratory. It also publishes cleaning and general buying guides...

 that said, "The transistors in this set have not been used in an effort to build the smallest radio on the market, and good performance has not been sacrificed." Following the success of the 8-TP-1, Zenith, RCA, DeWald, and Crosley began flooding the market with additional transistor radio models.


Prior to the Regency TR-1, transistors were difficult to produce. Only one in five transistors that were produced worked as expected (only a 20% yield) and as a result the price remained extremely high. When it was released in 1954, the Regency TR-1 cost $49.95 (roughly $364 in 2006 U.S. dollars) and sold about 150,000 units. Raytheon and Zenith Electronics transistor radios soon followed and were priced even higher. In 1955, Raytheon's 8-TR-1 was priced at $80 (approximately $425 in 1994 U.S. dollars). Sony's TR-63, released in December 1957 cost $39.95. Following the success of the TR-63 the Japanese companies continued to make their transistor radios smaller. Coupled with the extremely low labor costs in Japan, the Japanese transistor radios began selling for as low as $25. In 1962 American manufacturers dropped prices of transistor radios to as low as $15.

Japanese history in the market

While on a trip to the United States in 1952, Masura Ibuka, founder of Tokyo Telecommunications, discovered that AT&T was about to make licensing available for the transistor. Ibuka and physicist Akio Morita convinced the Ministry of International Trade and Industry (MITI) in Japan to finance the $25,000 licensing fee. For several months Ibuka traveled around the United States borrowing ideas from the American transistor manufacturers. Improving upon the ideas, Tokyo Telecommunications made its first functional transistor radio in 1954. Within five years, Tokyo Telecommunications grew from seven employees to approximately five hundred. Other Japanese companies soon followed their entry into the American market and the grand total of electronic products exported from Japan in 1958 increased 2.5 times in comparison to 1957.

TR-55 and TR-7

In August 1955, still a small company named Tokyo Tsushin Kogyo, Ltd. (Tokyo Telecommunications Engineering Corporation), Ibuka and Morita introduced their own five-transistor radio into the U.S. market, the TR-55
The TR-55, released in 1955, was Sony's first transistor radio, and the first to be made in Japan. The use of transistors rather than vacuum tubes allowed the device to be much smaller than earlier radios, and allowed them to be the first truly portable radio from Japan.-Technical...

, under the new brand name Sony. With its release, Sony became the first company to manufacture a radio from the transistors on up, and to utilize all miniature components. It is estimated that only 5,000 to 10,000 units were produced. Coupled by a lack of advertising the result was the demise of this initial attempt. In 1955, in addition to the TR-55, the TR-7 was introduced in the United States by Sony through trade magazines, but was as equally unsuccessful.


The TR-63 was introduced by Sony to the United States in December 1957. The TR-63 was 1/4" narrower and 1/2" shorter than the original Regency TR-1. Like the TR-1 it was offered in four colors: lemon, green, red, and black. In addition to its smaller size, the TR-63 had a small tuning capacitor and required a new nine-volt battery which would become the standard. Approximately 100,000 units of the TR-63 were imported in 1957. This "pocketable" (The term "pocketable" was a matter of some interpretation, as Sony allegedly had special shirts made with oversized pockets for their salesmen) model proved highly successful in the market. With the visible success of the TR-63 Japanese competitors such as Toshiba and Sharp joined the market. By 1959, in the United States market, there were more than six million transistor radio sets produced by Japanese companies that represented $62 million in revenue.

In popular culture

Transistor radios were extremely successful because of four social forces — a large number of young people, a post-World War II baby boom, a public with a disposable income amidst a period of prosperity, and the growing popularity of rock 'n' roll music. The transistor radio appeared in many popular films such as Lolita
Lolita (1962 film)
Lolita is a 1962 comedy-drama film by Stanley Kubrick based on the classic novel of the same title by Vladimir Nabokov. The film stars James Mason as Humbert Humbert, Sue Lyon as Dolores Haze and Shelley Winters as Charlotte Haze with Peter Sellers as Clare Quilty.Due to the MPAA's restrictions at...

and the term "transistor radio" can be heard in the lyrics of Van Morrison's "Brown-Eyed Girl", a famous top 10 Billboard hit in the late 1960s.
Starting in 1954, transistor radios took on more elaborate designs as a result of heated competition. Eventually, transistor radios doubled as novelty items. The small components of transistor radios that became smaller over time were used to make anything from "Jimmy Carter Peanut-shaped" radios to "Gun-shaped" radios to "Mork from Ork Eggship-shaped" radios. Corporations used transistor radios to advertise their business. "Charlie the Tuna-shaped" radios could be purchased from Star-Kist for an insignificant amount of money giving their company visibility amongst the public. These novelty radios are now bought and sold as collector's items amongst modern day collectors.

Transistor radio decline

The emergence of Hong Kong in the transistor radio market resulted in the decline of Japanese participation in the late-1960's. Japan continued to dominate the electronics and semiconductor markets, but now shied away from radio manufacturing leaving production to not only Hong Kong, but also Korea, Taiwan, and other Pacific Rim countries who picked up where Japan left off. Currently, China is the foremost producer of transistor radios. In 1970 the last assembly line producing transistor radios in America shut down. The Zenith Trans-Oceanic 7000 was the last American-made transistor radio.

Rise of digital audio players

Use of air signal only radios (AM/FM) have declined in popularity with the rise of portable digital audio players, which allow users to carry and listen to the music of their choosing and may also include a radio tuner. This is a popular choice with listeners who are dissatisfied with terrestrial music radio because of a limited selection of music or other criticisms. However, transistor radios are still popular for news, talk radio
Talk radio
Talk radio is a radio format containing discussion about topical issues. Most shows are regularly hosted by a single individual, and often feature interviews with a number of different guests. Talk radio typically includes an element of listener participation, usually by broadcasting live...

, weather, live sporting events and emergency alert applications.

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)
  • 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. (, 2002).
  • The Regency TR-1 story, based on an interview with Regency co-founder, John Pies (partner with Joe Weaver)

External links

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