THE INCREDIBLE STORY BEHIND THE FIRST TRANSISTOR RADIO

IEEE Spectrum - Monday, September 30, 2024 at 10:00 AM The Incredible Story Behind the First Transistor Radio Imagine if your boss called a meeting in May to announce that he’s committing 10 percent of the company’s revenue to the development of a brand-new mass-market consumer product, made with a not-yet-ready-for-mass-production component. Oh, and he wants it on store shelves in less than six months, in time for the holiday shopping season. Ambitious, yes. Kind of nuts, also yes. But that’s pretty much what Pat Haggerty, vice president of Texas Instruments, did in 1954. The result was the Regency TR-1 <https://www.si.edu/object/regency-model-tr-1-transistor-radio%3Anmah_713528>; , the world’s first commercial transistor <https://spectrum.ieee.org/tag/transistor>; radio, which debuted 70 years ago this month. The engineers delivered on Haggerty’s audacious goal, and I certainly hope they received a substantial year-end bonus. Why did Texas Instruments make the Regency TR-1 transistor radio? But how did Texas Instruments come to make a transistor radio in the first place? TI traces its roots to a company called Geophysical Service Inc. (GSI), which made seismic instrumentation for the oil industry as well as electronics for the military. In 1945, GSI hired Patrick E. Haggerty <https://ethw.org/Patrick_E._Haggerty>; as the general manager of its laboratory and manufacturing division and its electronics work. By 1951, Haggerty’s division was significantly outpacing GSI’s geophysical division, and so the Dallas-based company reorganized as Texas Instruments to focus on electronics. Meanwhile, on 30 June 1948, Bell Labs announced John Bardeen and Walter Brattain’s game-changing invention of the transistor <https://spectrum.ieee.org/transistor-history>; . No longer would electronics be dependent on large, hot vacuum tubes. The U.S. government chose not to classify the technology because of its potentially broad applications. In 1951, Bell Labs began licensing the transistor <https://www.computerhistory.org/siliconengine/bell-labs-licenses-transistor-technology/>; for US $25,000 through the Western Electric Co.; Haggerty bought a license for TI the following year. The engineers delivered on Haggerty’s audacious goal, and I certainly hope they received a substantial year-end bonus. TI was still a small company, with not much in the way of R&D capacity. But Haggerty and the other founders wanted it to become a big and profitable company. And so they established research labs to focus on semiconductor materials and a project-engineering group to develop marketable products. The TR-1 was the first transistor radio, and it ignited a desire for portable gadgets that continues to this day.Bettmann/Getty Images Haggerty made a good investment when he hired Gordon Teal <https://ethw.org/Gordon_Teal>; , a 22-year veteran of Bell Labs. Although Teal wasn’t part of the team that invented the germanium transistor <https://spectrum.ieee.org/the-lost-history-of-the-transistor>; , he recognized that it could be improved by using a single grown crystal, such as silicon. Haggerty was familiar with Teal’s work from a 1951 Bell Labs symposium on transistor technology. Teal happened to be homesick for his native Texas, so when TI advertised for a research director in the New York Times, he applied, and Haggerty offered him the job of assistant vice president instead. Teal started at TI on 1 January 1953. Fifteen months later, Teal gave Haggerty a demonstration of the first silicon transistor, and he presented his findings three and a half weeks later at the Institute of Radio Engineers’ National Conference on Airborne Electronics, in Dayton, Ohio. His innocuously titled paper, “Some Recent Developments in Silicon and Germanium Materials and Devices,” completely understated the magnitude of the announcement. The audience was astounded to hear that TI had not just one but three types of silicon transistors already in production, as Michael Riordan recounts in his excellent article “The Lost History of the Transistor <https://spectrum.ieee.org/the-lost-history-of-the-transistor>; ” (IEEE Spectrum <https://spectrum.ieee.org/>; , October 2004). And fun fact: The TR-1 shown at top once belonged to Willis Adcock <https://ethw.org/Oral-History:Willis_Adcock>; , a physical chemist hired by Teal to perfect TI’s silicon transistors as well as transistors for the TR-1. (The radio is now in the collections of the Smithsonian’s National Museum of American History <https://americanhistory.si.edu/collections/nmah_713528>; .) The TR-1 became a product in less than six months This advancement in silicon put TI on the map as a major player in the transistor industry, but Haggerty was impatient. He wanted a transistorized commercial product now, even if that meant using germanium transistors. On 21 May 1954, Haggerty challenged a research group at TI to have a working prototype of a transistor radio by the following week; four days later, the team came through, with a breadboard containing eight transistors. Haggerty decided that was good enough to commit $2 million—just under 10 percent of TI’s revenue—to commercializing the radio. Of course, a working prototype is not the same as a mass-production product, and Haggerty knew TI needed a partner to help manufacture the radio. That partner turned out to be Industrial Development Engineering Associates (IDEA), a small company out of Indianapolis that specialized in antenna boosters and other electronic goods. They signed an agreement in June 1954 with the goal of announcing the new radio in October. TI would provide the components, and IDEA would manufacture the radio under its Regency brand. Germanium transistors at the time cost $10 to $15 apiece. With eight transistors, the radio was too expensive to be marketed at the desired price point of $50 (more than $580 today, which is coincidentally about what it’ll cost you to buy one in good condition on eBay). Vacuum-tube radios were selling for less, but TI and IDEA figured early adopters would pay that much to try out a new technology. Part of Haggerty’s strategy was to increase the volume of transistor production to eventually lower the per-transistor cost, which he managed to push down to about $2.50. By the time TI met with IDEA, the breadboard was down to six transistors. It was IDEA’s challenge to figure out how to make the transistorized radio at a profit. According to an oral history with Richard Koch <https://ethw.org/Oral-History:Richard_Koch>; , IDEA’s chief engineer on the project, TI’s real goal was to make transistors, and the radio was simply the gimmick to get there. In fact, part of the TI–IDEA agreement was that any patents that came out of the project would be in the public domain so that TI was free to sell more transistors to other buyers. At the initial meeting, Koch, who had never seen a transistor before in real life, suggested substituting a germanium diode for the detector (which extracted the audio signal from the desired radio frequency), bringing the transistor count down to five. After thinking about the configuration a bit more, Koch eliminated another transistor by using a single transistor for the oscillator/mixer circuit. TI’s original prototype used eight germanium transistors, which engineers reduced to six and, ultimately, four for the production model.Division of Work and Industry/National Museum of American History/Smithsonian Institution The final design was four transistors set in a superheterodyne design <https://ethw.org/Superheterodyne_Receiver>; , a type of receiver that combines two frequencies to produce an intermediate frequency that can be easily amplified, thereby boosting a weak signal and decreasing the required antenna size. The TR-1 had two transistors as intermediate-frequency amplifiers and one as an audio amplifier, plus the oscillator/mixer. Koch applied for a patent <https://patentimages.storage.googleapis.com/09/9c/20/f824ecdddc2ccc/US2892931.pdf>; for the circuitry the following year. The radio ran on a 22.5-volt battery, which offered a playing life of 20 to 30 hours and cost about $1.25. (Such batteries were also used in the external power and electronics pack for hearing aids, the only other consumer product to use transistors up until this point.) While IDEA’s team was working on the circuitry, they outsourced the design of the TR-1’s packaging <https://www.chicagodesignstories.com/post/who-designed-the-tr-1>; to the Chicago firm of Painter, Teague, and Petertil. Their first design didn’t work because the components didn’t fit. Would their second design be better? As Koch later recalled, IDEA’s purchasing agent, Floyd Hayhurst, picked up the molding dies for the radio cases in Chicago and rushed them back to Indianapolis. He arrived at 2:00 in the morning, and the team got to work. Fortunately, everything fit this time. The plastic case was a little warped, but that was simple to fix: They slapped a wooden piece on each case as it came off the line so it wouldn’t twist as it cooled. This video shows how each radio was assembled by hand: [embedded content] On 18 October 1954, Texas Instruments announced the first commercial transistorized radio. It would be available in select outlets in New York and Los Angeles beginning 1 November, with wider distribution once production ramped up. The Regency TR-1 Transistor Pocket Radio initially came in black, gray, red, and ivory. They later added green and mahogany, as well as a run of pearlescents and translucents: lavender, pearl white, meridian blue, powder pink, and lime. The TR-1 got so-so reviews, faced competition Consumer Reports was not enthusiastic about the Regency TR-1. In its April 1955 review, it found that transmission of speech was “adequate” under good conditions, but music transmission was unsatisfactory under any conditions, especially on a noisy street or crowded beach. The magazine used adjectives such as whistle, squeal, thin, tinny, and high-pitched to describe various sounds—not exactly high praise for a radio. It also found fault with the on/off switch. Their recommendation: Wait for further refinement before buying one. More than 100,000 TR-1s were sold in its first year, but the radio was never very profitable.Archive PL/Alamy The engineers at TI and IDEA didn’t necessarily disagree. They knew they were making a sound-quality trade-off by going with just four transistors. They also had quality-control problems with the transistors and other components, with initial failure rates up to 50 percent. Eventually, IDEA got the failure rate down to 12 to 15 percent. Unbeknownst to TI or IDEA, Raytheon was also working on a transistorized radio—a tabletop model <https://www.abetterpage.com/wt/us/Ray8TP.html>; rather than a pocket-size one. That gave them the space to use six transistors, which significantly upped the sound quality. Raytheon’s radio came out in February 1955. Priced at $79.95, it weighed 2 kilograms and ran on four D-cell batteries. That August, a small Japanese company called Tokyo Telecommunications Engineering Corp. <https://www.sony.com/en/SonyInfo/CorporateInfo/History/>; released its first transistor radio, the TR-55 <https://en.wikipedia.org/wiki/TR-55>; . A few years later, the company changed its name to Sony and went on to dominate the world’s consumer radio market. The legacy of the Regency TR-1 The Regency TR-1 was a success by many measures: It sold 100,000 in its first year, and it helped jump-start the transistor market. But the radio was never very profitable. Within a few years, both Texas Instruments and IDEA left the commercial AM radio business, TI to focus on semiconductors <https://spectrum.ieee.org/topic/semiconductors/>; , and IDEA to concentrate on citizens band radios. Yet Pat Haggerty estimated that this little pocket radio pushed the market in transistorized consumer goods ahead by two years. It was a leap of faith that worked out, thanks to some hardworking engineers with a vision. Part of a continuing series <https://spectrum.ieee.org/collections/past-forward/>; looking at historical artifacts that embrace the boundless potential of technology. An abridged version of this article appears in the October 2024 print issue as “The First Transistor Radio.” From Your Site Articles Related Articles Around the Web https://spectrum.ieee.org/transistor-radio-invented