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Announced on this day, October 18, 1954: the transistor radio
Transistor radio
A classic Emerson transistor radio, circa 1958
A transistor radio is a small portable radio receiver that uses transistor-based circuitry. Following the invention of the transistor, the first commercial transistor radio was released in 1954. The mass-market success of the smaller and cheaper Sony TR-63, released in 1957, led to the transistor radio becoming the most popular electronic communication device of the 1960s and 1970s. Transistor radios are still commonly used as car radios. Billions of transistor radios are estimated to have been sold worldwide between the 1950s and 2012.
The pocket size of transistor radios sparked a change in popular music listening habits, allowing people to listen to music anywhere they went. Beginning in the 1980s, however, cheap AM transistor radios were superseded by devices with higher audio quality such as portable CD players, personal audio players, boomboxes, and (eventually) smartphones, some of which contain radios themselves.
Background
Before the transistor was invented, radios used vacuum tubes. Although portable vacuum tube radios were produced, they were typically bulky and heavy. The need for a low voltage high current source to power the filaments of the tubes and high voltage for the anode potential typically required two batteries. Vacuum tubes were also inefficient and fragile compared to transistors, and had a limited lifetime.
Bell Laboratories demonstrated the first transistor on December 23, 1947. The scientific team at Bell Laboratories responsible for the solid-state amplifier included William Shockley, Walter Houser Brattain, and John Bardeen. 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 (originally Tokyo Telecommunications Engineering Corporation). Texas Instruments had demonstrated all-transistor AM (amplitude modulation) radios as early as May 25, 1954, 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 Radio Fair by the German firm Intermetall. It was built with four of Intermetall's hand-made transistors, based upon the 1948 invention of the "Transistron"-germanium point-contact transistor by Herbert Mataré and Heinrich Welker. 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 Division of I.D.E.A., were the first to offer a production model starting in October 1954.
The use of transistors instead of vacuum tubes 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. Since the transistor base draws current, its input impedance is low in contrast to the high input 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 radio 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 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. 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.
Early commercial transistor radios
Regency TR-1.
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, 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. 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. (The Chief Project Engineer for the radio design at Texas Instruments' headquarters in Dallas, Texas was Paul D. Davis, Jr., who had a degree in Electrical Engineering from Southern Methodist University. He was assigned the project due to his experience with radio engineering in World War II.) 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 reported in 1954 that "the radio has only four transistors. One acts as 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, US 2892931, former Project Engineer of I.D.E.A.
....
A classic Emerson transistor radio, circa 1958
A transistor radio is a small portable radio receiver that uses transistor-based circuitry. Following the invention of the transistor, the first commercial transistor radio was released in 1954. The mass-market success of the smaller and cheaper Sony TR-63, released in 1957, led to the transistor radio becoming the most popular electronic communication device of the 1960s and 1970s. Transistor radios are still commonly used as car radios. Billions of transistor radios are estimated to have been sold worldwide between the 1950s and 2012.
The pocket size of transistor radios sparked a change in popular music listening habits, allowing people to listen to music anywhere they went. Beginning in the 1980s, however, cheap AM transistor radios were superseded by devices with higher audio quality such as portable CD players, personal audio players, boomboxes, and (eventually) smartphones, some of which contain radios themselves.
Background
Before the transistor was invented, radios used vacuum tubes. Although portable vacuum tube radios were produced, they were typically bulky and heavy. The need for a low voltage high current source to power the filaments of the tubes and high voltage for the anode potential typically required two batteries. Vacuum tubes were also inefficient and fragile compared to transistors, and had a limited lifetime.
Bell Laboratories demonstrated the first transistor on December 23, 1947. The scientific team at Bell Laboratories responsible for the solid-state amplifier included William Shockley, Walter Houser Brattain, and John Bardeen. 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 (originally Tokyo Telecommunications Engineering Corporation). Texas Instruments had demonstrated all-transistor AM (amplitude modulation) radios as early as May 25, 1954, 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 Radio Fair by the German firm Intermetall. It was built with four of Intermetall's hand-made transistors, based upon the 1948 invention of the "Transistron"-germanium point-contact transistor by Herbert Mataré and Heinrich Welker. 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 Division of I.D.E.A., were the first to offer a production model starting in October 1954.
The use of transistors instead of vacuum tubes 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. Since the transistor base draws current, its input impedance is low in contrast to the high input 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 radio 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 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. 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.
Early commercial transistor radios
Regency TR-1.
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, 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. 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. (The Chief Project Engineer for the radio design at Texas Instruments' headquarters in Dallas, Texas was Paul D. Davis, Jr., who had a degree in Electrical Engineering from Southern Methodist University. He was assigned the project due to his experience with radio engineering in World War II.) 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 reported in 1954 that "the radio has only four transistors. One acts as 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, US 2892931, former Project Engineer of I.D.E.A.
....
Regency TR-1
Regency TR-1 transistor radio
The Regency TR-1 was the first commercially manufactured transistor radio. First sold in 1954, it was a novelty due to small size and portability; about 150,000 units were sold despite mediocre performance. The device demonstrated the use of transistors for consumer electronics; previously transistors had only been used in military or industrial applications. Surviving specimens are sought out by collectors.
History
Regency TR1 schematic
Two companies—Texas Instruments of Dallas, Texas, and Industrial Development Engineering Associates (I.D.E.A.) of Indianapolis, Indiana—worked together to produce the Regency TR-1. Previously, Texas Instruments produced instrumentation for the oil industry and locating devices for the U.S. Navy—and I.D.E.A. built home television antenna boosters. The two companies worked together on the TR-1 to grow revenues for their respective companies by pioneering this new product area.
In May 1954, Texas Instruments had designed and built a prototype transistor radio and was looking for an established radio manufacturer to develop and market a radio using their transistors. No major radio maker, including RCA, Philco, and Emerson, was 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 would be "20 million radios in three years." The Regency Division of I.D.E.A announced the TR-1 on October 18, 1954, and put it on sale in November 1954. It was the first practical transistor radio made in significant numbers.
One year after the TR-1 release, sales approached 100,000 units. The look and size of the TR-1 were well received, but reviews of its performance were typically adverse. The Regency TR-1 is patented by Richard C. Koch, US 2892931, former Project Engineer of I.D.E.A.
The Regency TR-1 circuitry was refined from the Texas Instruments prototype, reducing the number of parts, including two expensive transistors. Though this severely reduced the audio output volume, it let I.D.E.A. sell the radio for only a small profit. The initial TR-1 retail price was $49.95 (roughly $443 in year-2016 dollars) and it sold about 150,000 units.
The TR-1 uses Texas Instruments' NPN transistors, hand-picked in sets of four. A 22.5 volt battery provides power, since the only way to get adequate radio frequency performance out of early transistors was to run them close to their collector-to-emitter breakdown voltage. The current drain from this battery is only 4 mA, allowing 20 to 30 hours of operation, in comparison to only several hours for the portable receivers based on vacuum tubes.
While the radio was praised for novelty and small size, the sensitivity and sound quality were behind the tube-based competitors. A review in Consumer Reports mentions the high level of noise and instability on certain radio frequencies, recommending against the purchase.
Regency TR-1 transistor radio
The Regency TR-1 was the first commercially manufactured transistor radio. First sold in 1954, it was a novelty due to small size and portability; about 150,000 units were sold despite mediocre performance. The device demonstrated the use of transistors for consumer electronics; previously transistors had only been used in military or industrial applications. Surviving specimens are sought out by collectors.
History
Regency TR1 schematic
Two companies—Texas Instruments of Dallas, Texas, and Industrial Development Engineering Associates (I.D.E.A.) of Indianapolis, Indiana—worked together to produce the Regency TR-1. Previously, Texas Instruments produced instrumentation for the oil industry and locating devices for the U.S. Navy—and I.D.E.A. built home television antenna boosters. The two companies worked together on the TR-1 to grow revenues for their respective companies by pioneering this new product area.
In May 1954, Texas Instruments had designed and built a prototype transistor radio and was looking for an established radio manufacturer to develop and market a radio using their transistors. No major radio maker, including RCA, Philco, and Emerson, was 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 would be "20 million radios in three years." The Regency Division of I.D.E.A announced the TR-1 on October 18, 1954, and put it on sale in November 1954. It was the first practical transistor radio made in significant numbers.
One year after the TR-1 release, sales approached 100,000 units. The look and size of the TR-1 were well received, but reviews of its performance were typically adverse. The Regency TR-1 is patented by Richard C. Koch, US 2892931, former Project Engineer of I.D.E.A.
The Regency TR-1 circuitry was refined from the Texas Instruments prototype, reducing the number of parts, including two expensive transistors. Though this severely reduced the audio output volume, it let I.D.E.A. sell the radio for only a small profit. The initial TR-1 retail price was $49.95 (roughly $443 in year-2016 dollars) and it sold about 150,000 units.
The TR-1 uses Texas Instruments' NPN transistors, hand-picked in sets of four. A 22.5 volt battery provides power, since the only way to get adequate radio frequency performance out of early transistors was to run them close to their collector-to-emitter breakdown voltage. The current drain from this battery is only 4 mA, allowing 20 to 30 hours of operation, in comparison to only several hours for the portable receivers based on vacuum tubes.
While the radio was praised for novelty and small size, the sensitivity and sound quality were behind the tube-based competitors. A review in Consumer Reports mentions the high level of noise and instability on certain radio frequencies, recommending against the purchase.
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