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Information about Transistor Radio

''This article is about an electronic device. For the fourth studio album by M. Ward, see Transistor Radio.
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Regency TR-1.
A transistor radio is a small transistor-based radio receiver. Historically, the term "transistor radio" refers to a radio that is monoaural and typically receives only the 540–1600 kilocycle[1] AM broadcast band.

History

In 1952 Intermetall unveiled what was probably the first transistorized portable radio on the Düsseldorf Radio fair.

The first commercial transistor radio, the Regency TR-1, was announced on October 18, 1954 by the Regency Division of Industrial Development Engineering Associates of Indianapolis, Indiana and put on sale in November of 1954. It cost $49.95 (the equivalent of roughly $364 in year-2005 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 by releasing the Sony TR-55 in August 1955 as Japan's first commercially produced transistor radio. 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" TR-63 released in March 1957, a model which proved highly successful in that market. In January 1958, the company changed its name to Sony, a 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.

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Sanyo 8S-P3.
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 the audio reception was available instantly, since there were no filaments concerned which could have taken considerable time to heat up. The typical portable 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 Cathode and rest of the circuitry. 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 resonance 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 (upto 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.

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A modern transistor radio (Sony Walkman SRF-S84 transistor radio, released 2001, without included earphones)
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 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 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.

Decline

Transistor radios have declined in popularity with the rise of portable digital audio players, which allow people to listen to the exact music of their choosing and may 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, soccer games, horse races and emergency alert applications.

See also

Notes

1. ^ 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.

External links

  • This is not an image, but rather a PDF file.

    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)
    • 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) www.regencytr1.com/Regency_Early_Years.html
    Transistor Radio is the fourth studio album by M. Ward.

    The first track is an instrumental cover of a track from The Beach Boys album Pet Sounds.

    The track "Here Comes the Sun Again" is featured in the commercial for the 2007 Cadillac SRX Crossover.
    ..... Click the link for more information.
    A transistor is a semiconductor device, commonly used as an amplifier or an electrically controlled switch. The transistor is the fundamental building block of the circuitry in computers, cellular phones, and all other modern electronic devices.
    ..... Click the link for more information.
    A radio receiver is an electronic circuit that receives its input from an antenna, uses electronic filters to separate a wanted radio signal from all other signals picked up by this antenna, amplifies it to a level suitable for further processing, and finally converts through
    ..... Click the link for more information.
    Radio is the wireless transmission of signals, by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space.
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    Monaural (often shortened to mono) sound reproduction is single-channel. Typically there is only one microphone, one loudspeaker, or, in the case of headphones or multiple loudspeakers, they are fed from a common signal path, and in the case of multiple microphones, mixed
    ..... Click the link for more information.
    For the song by Everclear, see .


    AM broadcasting is the process of radio broadcasting using Amplitude Modulation.

    History

    :
    Main article: History of radio

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    The Regency TR-1 was the first commercially produced portable transistor radio receiver. Announced on October 18th 1954 by the Regency Division of the Industrial Development Engineering Associates of Indianapolis production started in November 1954.
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    October 18 is the 1st day of the year (2nd in leap years) in the Gregorian calendar. There are 0 days remaining.

    Events


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    19th century - 20th century - 21st century
    1920s  1930s  1940s  - 1950s -  1960s  1970s  1980s
    1951 1952 1953 - 1954 - 1955 1956 1957

    Year 1954 (MCMLIV
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    City of Indianapolis

    Flag
    Seal
    Nickname: Indy, the Circle City, and (less commonly) Naptown
    Location in the state of Indiana
    Coordinates:
    Country
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    Raytheon Company

    Public (NYSE: RTN )
    Founded Cambridge, Massachusetts (1922)
    Headquarters Waltham, Massachusetts

    Key people William H. Swanson, Chairman and CEO
    Industry Aerospace and defense
    Products Conglomerate
    Revenue $20.
    ..... Click the link for more information.
    Zenith Electronics Corporation

    Electronics
    Founded 1918
    Headquarters Lincolnshire, Illinois, USA

    Revenue US$444.7 million (1999)
    Employees 976
    Parent LG Group
    Website Zenith Electronics

    Zenith Electronics Corporation
    ..... Click the link for more information.
    Texas Instruments

    Public (NYSE:  TXN )
    Founded 1930 (as GSI), 1951 (as TI)[1]
    Headquarters Dallas, Texas, USA

    Key people Tom Engibous, Chairman
    Rich Templeton, President & CEO
    Kevin March, CFO
    Brian Bonner, CIO
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    RCA, formerly an acronym for the Radio Corporation of America, is now a trademark owned by Thomson SA through RCA Trademark Management S.A., a company owned by Thomson.
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    Sony Corporation
    ソニー株式会?

    Public (TYO: 6758 ; NYSE:  SNE )
    Founded May 7 1946 (adopted current name in 1958) by Masaru Ibuka and Akio Morita[1]
    Headquarters Minato-ku, Tokyo, Japan[1]
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    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.
    ..... Click the link for more information.
    A transistor is a semiconductor device, commonly used as an amplifier or an electrically controlled switch. The transistor is the fundamental building block of the circuitry in computers, cellular phones, and all other modern electronic devices.
    ..... Click the link for more information.
    vacuum tube, electron tube (inside North America), thermionic valve, or just valve (elsewhere); is a device used to amplify, switch, otherwise modify, or create an electrical signal by controlling the movement of electrons in a low-pressure space, often not
    ..... Click the link for more information.
    battery is a device consisting of one or more electrochemical cells, which store chemical energy and make it available in an electrical form. There are many types of electrochemical cells, including galvanic cells, electrolytic cells, fuel cells, flow cells, and voltaic cells.
    ..... Click the link for more information.
    A cathode is an electrode through which (positive) electric current flows out of a polarized electrical device. Mnemonic: CCD (Cathode Current Departs). To dispel a common misconception, often incorrectly inferred from the correct fact that in all electrochemical
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    PP3 battery, commonly referred to simply as a nine-volt battery, is shaped as a rounded rectangular prism and has a nominal output of nine volts. Its nominal dimensions are 48 mm × 25 mm × 15 mm (ANSI standard 1604A).
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    Walkman is a popular Sony brand used to market its portable audio and video players. The original Walkman introduced a change in music listening habits, allowing people to carry their own choice of music with them.
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    Portable communications devices refer to hand-held or wearable devices. For example, the Walkie Talkie is a device that is hand-held when in use, and wearable when not in use. Portable telephones (cellular telephones) are also carried, or worn, on a belt, or in a pocket.
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    Medium wave or mediumwave (MW) is a part of the Medium frequency (MF) radio band used for AM broadcasting. For most of the world the frequencies used for broadcasting are from 520 kHz up to 1611 kHz, and in North America an extended AM broadcast band goes up to
    ..... Click the link for more information.
    In most of the world, the FM broadcast band, used for broadcasting FM radio stations, goes from 87.5 to 108.0 MHz. In Japan the FM broadcast band is 76–90 MHz, unlike any other country in the world. The old OIRT band in Eastern Europe was 65.8–74 MHz.
    ..... Click the link for more information.
    Shortwave radio operates between the frequencies of 3 MHz (3,000 kHz) and 30 MHz (30,000 kHz) [1] and came to be referred to as such in the early days of radio because the wavelengths associated with this frequency range were shorter than the long
    ..... Click the link for more information.
    battery is a device consisting of one or more electrochemical cells, which store chemical energy and make it available in an electrical form. There are many types of electrochemical cells, including galvanic cells, electrolytic cells, fuel cells, flow cells, and voltaic cells.
    ..... Click the link for more information.
    A transistor is a semiconductor device, commonly used as an amplifier or an electrically controlled switch. The transistor is the fundamental building block of the circuitry in computers, cellular phones, and all other modern electronic devices.
    ..... Click the link for more information.
    integrated circuit (also known as IC, microcircuit, microchip, silicon chip, or chip) is a miniaturized electronic circuit (consisting mainly of semiconductor devices, as well as passive components) that has been manufactured in the surface of a
    ..... Click the link for more information.
    MP3 player, a digital audio player or "DAP" is a portable, handheld digital music player that stores, organizes and plays MP3 and often other audio files. Most DAPs are powered by rechargeable batteries, some of which are not user replaceable.
    ..... Click the link for more information.


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