The First Transistor Radio: Engineering the Regency TR-1

Think about in case your boss known as a gathering in Could to announce that he’s committing 10 % of the corporate’s income to the event of a brand-new mass-market shopper product, made with a not-yet-ready-for-mass-production element. Oh, and he needs it on retailer cabinets in lower than six months, in time for the vacation buying season. Formidable, sure. Sort of nuts, additionally sure.

However that’s just about what Pat Haggerty, vice chairman of Texas Devices, did in 1954. The outcome was the
Regency TR-1, the world’s first industrial transistor radio, which debuted 70 years in the past this month. The engineers delivered on Haggerty’s audacious purpose, and I actually hope they acquired a considerable year-end bonus.

Why did Texas Devices make the Regency TR-1 transistor radio?

However how did Texas Devices come to make a transistor radio within the first place? TI traces its roots to an organization known as Geophysical Service Inc. (GSI), which made seismic instrumentation for the oil business in addition to electronics for the navy. In 1945, GSI employed
Patrick E. Haggerty as the overall supervisor of its laboratory and manufacturing division and its electronics work. By 1951, Haggerty’s division was considerably outpacing GSI’s geophysical division, and so the Dallas-based firm reorganized as Texas Devices to deal with electronics.

In the meantime, on 30 June 1948, Bell Labs introduced John Bardeen and Walter Brattain’s
game-changing invention of the transistor. Not would electronics be depending on giant, scorching vacuum tubes. The U.S. authorities selected to not classify the know-how due to its doubtlessly broad functions. In 1951, Bell Labs started licensing the transistor for US $25,000 by way of the Western Electrical Co.; Haggerty purchased a license for TI the next 12 months.

The engineers delivered on Haggerty’s audacious purpose, and I actually hope they acquired a considerable year-end bonus.

TI was nonetheless a small firm, with not a lot in the best way of R&D capability. However Haggerty and the opposite founders wished it to turn into an enormous and worthwhile firm. And they also established analysis labs to deal with semiconductor supplies and a project-engineering group to develop marketable merchandise.

The TR-1 was the primary transistor radio, and it ignited a need for transportable devices that continues to at the present time.Bettmann/Getty Photos

Haggerty made a great funding when he employed
Gordon Teal, a 22-year veteran of Bell Labs. Though Teal wasn’t a part of the staff that invented the germanium transistor, he acknowledged that it may very well be improved through the use of a single grown crystal, equivalent to silicon. Haggerty was acquainted with Teal’s work from a 1951 Bell Labs symposium on transistor know-how. Teal occurred to be homesick for his native Texas, so when TI marketed for a analysis director within the New York Instances, he utilized, and Haggerty provided him the job of assistant vice chairman as an alternative. Teal began at TI on 1 January 1953.

Fifteen months later, Teal gave Haggerty an indication of the primary silicon transistor, and he offered his findings three and a half weeks later on the Institute of Radio Engineers’ Nationwide Convention on Airborne Electronics, in Dayton, Ohio. His innocuously titled paper, “Some Latest Developments in Silicon and Germanium Supplies and Gadgets,” utterly understated the magnitude of the announcement. The viewers was astounded to listen to that TI had not only one however three varieties of silicon transistors already in manufacturing, as Michael Riordan recounts in his wonderful article “The Misplaced Historical past of the Transistor” (IEEE Spectrum, October 2004).

And enjoyable reality: The TR-1 proven at high as soon as belonged to Willis Adcock, a bodily chemist employed by Teal to excellent TI’s silicon transistors in addition to transistors for the TR-1. (The radio is now within the collections of the Smithsonian’s Nationwide Museum of American Historical past.)

The TR-1 grew to become a product in lower than six months

This development in silicon put TI on the map as a serious participant within the transistor business, however Haggerty was impatient. He wished a transistorized industrial product
now, even when that meant utilizing germanium transistors. On 21 Could 1954, Haggerty challenged a analysis group at TI to have a working prototype of a transistor radio by the next week; 4 days later, the staff got here by way of, with a breadboard containing eight transistors. Haggerty determined that was ok to commit $2 million—slightly below 10 % of TI’s income—to commercializing the radio.

After all, a working prototype isn’t the identical as a mass-production product, and Haggerty knew TI wanted a accomplice to assist manufacture the radio. That accomplice turned out to be Industrial Improvement Engineering Associates (IDEA), a small firm out of Indianapolis that specialised in antenna boosters and different digital items. They signed an settlement in June 1954 with the purpose of asserting the brand new radio in October. TI would supply the parts, and IDEA would manufacture the radio beneath its Regency model.

Germanium transistors on the time price $10 to $15 apiece. With eight transistors, the radio was too costly to be marketed on the desired worth level of $50 (greater than $580 as we speak, which is coincidentally about what it’ll price you to purchase one in good situation on eBay). Vacuum-tube radios had been promoting for much less, however TI and IDEA figured early adopters would pay that a lot to check out a brand new know-how. A part of Haggerty’s technique was to extend the amount of transistor manufacturing to finally decrease the per-transistor price, which he managed to push all the way down to about $2.50.

By the point TI met with IDEA, the breadboard was down to 6 transistors. It was IDEA’s problem to determine the right way to make the transistorized radio at a revenue. In response to an
oral historical past with Richard Koch, IDEA’s chief engineer on the challenge, TI’s actual purpose was to make transistors, and the radio was merely the gimmick to get there. In actual fact, a part of the TI–IDEA settlement was that any patents that got here out of the challenge could be within the public area in order that TI was free to promote extra transistors to different consumers.

On the preliminary assembly, Koch, who had by no means seen a transistor earlier than in actual life, prompt substituting a germanium diode for the detector (which extracted the audio sign from the specified radio frequency), bringing the transistor depend down to 5. After desirous about the configuration a bit extra, Koch eradicated one other transistor through the use of a single transistor for the oscillator/mixer circuit.

TI’s unique prototype used eight germanium transistors, which engineers lowered to 6 and, in the end, 4 for the manufacturing mannequin.Division of Work and Business/Nationwide Museum of American Historical past/Smithsonian Establishment

The ultimate design was 4 transistors set in a
superheterodyne design, a sort of receiver that mixes two frequencies to provide an intermediate frequency that may be simply amplified, thereby boosting a weak sign and lowering the required antenna measurement. The TR-1 had two transistors as intermediate-frequency amplifiers and one as an audio amplifier, plus the oscillator/mixer. Koch utilized for a patent for the circuitry the next 12 months.

The radio ran on a 22.5-volt battery, which provided a taking part in lifetime of 20 to 30 hours and value about $1.25. (Such batteries had been additionally used within the exterior energy and electronics pack for listening to aids, the one different shopper product to make use of transistors up till this level.)

Whereas IDEA’s staff was engaged on the circuitry, they outsourced the
design of the TR-1’s packaging to the Chicago agency of Painter, Teague, and Petertil. Their first design didn’t work as a result of the parts didn’t match. Would their second design be higher? As Koch later recalled, IDEA’s buying agent, Floyd Hayhurst, picked up the molding dies for the radio instances in Chicago and rushed them again to Indianapolis. He arrived at 2:00 within the morning, and the staff started working. Fortuitously, all the pieces match this time. The plastic case was a little bit warped, however that was easy to repair: They slapped a wood piece on every case because it got here off the road so it wouldn’t twist because it cooled.

This video reveals how every radio was assembled by hand:

On 18 October 1954, Texas Devices introduced the primary industrial transistorized radio. It could be accessible in choose shops in New York and Los Angeles starting 1 November, with wider distribution as soon as manufacturing ramped up. The Regency TR-1 Transistor Pocket Radio initially got here in black, grey, crimson, and ivory. They later added inexperienced and mahogany, in addition to a run of pearlescents and translucents: lavender, pearl white, meridian blue, powder pink, and lime.

The TR-1 acquired so-so opinions, confronted competitors

Client Studies was not enthusiastic concerning the Regency TR-1. In its April 1955 assessment, it discovered that transmission of speech was “satisfactory” beneath good situations, however music transmission was unsatisfactory beneath any situations, particularly on a loud road or crowded seaside. The journal used adjectives equivalent to whistle, squeal, skinny, tinny, and high-pitched to explain numerous sounds—not precisely excessive reward for a radio. It additionally discovered fault with the on/off change. Their advice: Await additional refinement earlier than shopping for one.

Greater than 100,000 TR-1s had been bought in its first 12 months, however the radio was by no means very worthwhile.Archive PL/Alamy

The engineers at TI and IDEA didn’t essentially disagree. They knew they had been making a sound-quality trade-off by going with simply 4 transistors. In addition they had quality-control issues with the transistors and different parts, with preliminary failure charges as much as 50 %. Finally, IDEA acquired the failure fee all the way down to 12 to fifteen %.

Unbeknownst to TI or IDEA, Raytheon was additionally engaged on a transistorized radio—a tabletop mannequin fairly than a pocket-size one. That gave them the house to make use of six transistors, which considerably upped the sound high quality. Raytheon’s radio got here out in February 1955. Priced at $79.95, it weighed 2 kilograms and ran on 4 D-cell batteries. That August, a small Japanese firm known as Tokyo Telecommunications Engineering Corp. launched its first transistor radio, the TR-55. A couple of years later, the corporate modified its identify to Sony and went on to dominate the world’s shopper radio market.

The legacy of the Regency TR-1

The Regency TR-1 was a hit by many measures: It bought 100,000 in its first 12 months, and it helped jump-start the transistor market. However the radio was by no means very worthwhile. Inside a couple of years, each Texas Devices and IDEA left the industrial AM radio enterprise, TI to deal with semiconductors, and IDEA to focus on residents band radios. But Pat Haggerty estimated that this little pocket radio pushed the market in transistorized shopper items forward by two years. It was a leap of religion that labored out, due to some hardworking engineers with a imaginative and prescient.

A part of a persevering with sequence taking a look at historic artifacts that embrace the boundless potential of know-how.

An abridged model of this text seems within the October 2024 print challenge as “The First Transistor Radio.”