Transistor radio

The invention:



 Miniature portable radio that used transistors and

created a new mass market for electronic products.









The people behind the invention:



John Bardeen (1908-1991), an American physicist

Walter H. Brattain (1902-1987), an American physicist

William Shockley (1910-1989), an American physicist

Akio Morita (1921-1999), a Japanese physicist and engineer

Masaru Ibuka (1907-1997), a Japanese electrical engineer and

industrialist





A Replacement for Vacuum Tubes



The invention of the first transistor by William Shockley, John

Bardeen, andWalter H. Brattain of Bell Labs in 1947 was a scientific

event of great importance. Its commercial importance at the time,

however, was negligible. The commercial potential of the transistor

lay in the possibility of using semiconductor materials to carry out

the functions performed by vacuum tubes, the fragile and expensive

tubes that were the electronic hearts of radios, sound amplifiers,

and telephone systems. Transistors were smaller, more rugged,

and less power-hungry than vacuum tubes. They did not suffer

from overheating. They offered an alternative to the unreliability

and short life of vacuum tubes.

Bell Labs had begun the semiconductor research project in an effort

to find a better means of electronic amplification. This was

needed to increase the strength of telephone signals over long distances.

Therefore, the first commercial use of the transistor was

sought in speech amplification, and the small size of the device

made it a perfect component for hearing aids. Engineers from the

Raytheon Company, the leading manufacturer of hearing aids, were

invited to Bell Labs to view the new transistor and to help assess the

commercial potential of the technology. The first transistorized consumer

product, the hearing aid, was soon on the market. The early

models built by Raytheon used three junction-type transistors and

cost more than two hundred dollars. They were small enough to go

directly into the ear or to be incorporated into eyeglasses.

The commercial application of semiconductors was aimed largely

at replacing the control and amplification functions carried out by

vacuum tubes. The perfect vehicle for this substitution was the radio

set. Vacuum tubes were the most expensive part of a radio set

and the most prone to break down. The early junction transistors

operated best at low frequencies, and subsequently more research

was needed to produce a commercial high-frequency transistor.

Several of the licensees embarked on this quest, including the Radio

Corporation of America (RCA), Texas Instruments, and the Tokyo

Telecommunications Engineering Company of Japan.



Perfecting the Transistor



The Tokyo Telecommunications Engineering Company of Japan,

formed in 1946, had produced a line of instruments and consumer

products based on vacuum-tube technology. Its most successful

product was a magnetic tape recorder. In 1952, one of the founders

of the company, Masaru Ibuka, visited the United States to learn

more about the use of tape recorders in schools and found out that

Western Electric was preparing to license the transistor patent.With

only the slightest understanding of the workings of semiconductors,

Tokyo Telecommunications purchased a license in 1954 with

the intention of using transistors in a radio set.

The first task facing the Japanese was to increase the frequency

response of the transistor to make it suitable for radio use. Then a

method of manufacturing transistors cheaply had to be found. At

the time, junction transistors were made from slices of germanium

crystal. Growing the crystal was not an exact science, nor was the

process of “doping” it with impurities to form the different layers of

conductivity that made semiconductors useful. The Japanese engineers

found that the failure rate for high-frequency transistors was

extremely high. The yield of good transistors from one batch ran as

low as 5 percent, which made them extremely expensive and put the

whole project in doubt. The effort to replace vacuum tubes with

components made of semiconductors was motivated by cost rather

than performance; if transistors proved to be more expensive, then

it was not worth using them.

Engineers from Tokyo Telecommunications again came to the

United States to search for information about the production of

transistors. In 1954, the first high-frequency transistor was produced

in Japan. The success of Texas Instruments in producing the

components for the first transistorized radio (introduced by the Regency

Company in 1954) spurred the Japanese to greater efforts.

Much of their engineering and research work was directed at the

manufacture and quality control of transistors. In 1955, they introduced

their transistor radio, the TR-55, which carried the brand

name “Sony.” The name was chosen because the executives of the

company believed that the product would have an international appeal

and therefore needed a brand name that could be recognized

easily and remembered in many languages. In 1957, the name of the

entire company was changed to Sony.



Impact



Although Sony’s transistor radios were successful in the marketplace,

they were still relatively large and cumbersome. Ibuka saw a

consumer market for a miniature radio and gave his engineers the

task of designing a radio small enough to fit into a shirt pocket. The

realization of this design—“Transistor Six”—was introduced in 1957.

It was an immediate success. Sony sold the radios by the millions,

and numerous imitations were also marketed under brand names

such as “Somy” and “Sonny.” The product became an indispensable

part of popular culture of the late 1950’s and 1960’s; its low cost enabled

the masses to enjoy radio wherever there were broadcasts.

The pocket-sized radio was the first of a line of electronic consumer

products that brought technology into personal contact with

the user. Sony was convinced that miniaturization did more than

make products more portable; it established a one-on-one relationship

between people and machines. Sony produced the first alltransistor

television in 1960. Two years later, it began to market a

miniature television in the United States. The continual reduction in

the size of Sony’s tape recorders reached a climax with the portable

tape player introduced in the 1980’s. The SonyWalkman was a marketing

triumph and a further reminder that Japanese companies led

the way in the design and marketing of electronic products.





John Bardeen





The transistor reduced the size of electronic circuits and at

the same time the amount of energy lost from them as heat.

Superconduction gave rise to electronic circuits with practically

no loss of energy at all. John Bardeen helped unlock the secrets

of both.

Bardeen was born in 1908 in Madison,Wisconsin, where his

mother was an artist and his father was a professor of anatomy

at the University ofWisconsin. Bardeen attended the university,

earning a bachelor’s degree in electrical engineering in 1928

and a master’s degree in geophysics in 1929. After working as a

geophysicist, he entered Princeton University, studying with

Eugene Wigner, the leading authority on solid-state physics,

and received a doctorate in mathematics and physics in 1936.

Bardeen taught at Harvard University and the University of

Minnesota until World War II, when he moved to the Naval

Ordnance Laboratory. Finding academic salaries too low to

support his family after the war, he accepted a position at Bell

Telephone Laboratories. There, with Walter Brattain, he turned

William Shockley’s theory of semiconductors into a practical

device—the transfer resistor, or transistor.

He returned to academia as a professor at the University of

Illinois and began to investigate a long-standing mystery in

physics, superconductivity, with a postdoctoral associate, Leon

Cooper, and a graduate student, J. Robert Schrieffer. In 1956

Cooper made a key discovery—superconducting electrons

travel in pairs. And while Bardeen was in Stockholm, Sweden,

collecting a share of the 1956 Nobel Prize in Physics for his work

on transistors, Schrieffer worked out a mathematical analysis of

the phenomenon. The theory that the three men published since

became known as BCS theory from the first letters of their last

names, and as well as explain superconductors, it pointed toward

a great deal of technology and additional basic research.

The team won the 1972 Nobel Prize in Physics for BCS theory,

making Bardeen the only person to ever win two Nobel Prizes

for physics. He retired in 1975 and died sixteen years later.





See also :  Compact disc; FM radio; Radio; Radio crystal sets; Television;

Transistor;



Further Reading



Handy, Roger, Maureen Erbe, and Aileen Antonier. Made in Japan:

Transistor Radios of the 1950s and 1960s. San Francisco: Chronicle

Books, 1993.



Marshall, David V. Akio Morita and Sony. Watford: Exley, 1995.

Morita, Akio, with Edwin M. Reingold, and Mitsuko Shimomura.

Made in Japan: Akio Morita and Sony. London: HarperCollins, 1994.









Nathan, John. Sony: The Private Life. London: HarperCollins-

Business, 2001.