Friday, October 29, 2021

The evolution of electronic device miniaturization

© Mark Ollig


The dawn of pocket-sized radios came into prominence due to the invention of the small, cylindrical electronic component called a transistor.

“My first transistor radio. First time ever I held a gadget in my hand. I loved what it could do. It brought me music, it opened up my world. I looked at my little radio and it had six transistors in it,” Apple Computer co-founder Steve Wozniak said in 2010.

Microsoft co-founder Bill Gates said, “Without the invention of the transistor, I’m quite sure that the PC would not exist as we know it today.”

Back in 1946, vacuum tubes were used in the electrical devices of the day. But, unfortunately, they were large and not suitable for small, portable devices. In addition, the glass vacuum tubes were expensive, fragile, used a lot of electricity, gave off a great deal of heat, were prone to recurrent failures, and regularly needed replacement.

At Bell Telephone Laboratories in New Jersey, scientist John Bardeen and physicist Walter Brattain developed a small electronic device Dec. 16, 1947, later called a point-contact transistor, using a silicon semiconductor, tiny wires, and a thin metal plate.

Further adjustments included attaching two small metal electrodes into each end of a slice of germanium (instead of silicon) one-half an inch long. Next, they used a thin strip of gold foil wrapped around a plastic triangle with a gap in the foil just above the middle of the germanium.

After applying a voltage, the screen on their oscilloscope showed the electrical power output through the piece of germanium was 100 times stronger than what went in. Thus, their invention was the first solid-state transistor using three electrical leads known as the emitter, the collector, and the base. As a result, the transistor could amplify and control the electrical signals going through it.

Bardeen, Brattain, and physicist William Shockley completed the invention of the transistor Dec. 23, 1947.

Credit for the name, transistor, comes from Bell Lab’s electrical engineer John R. Pierce, who came up with the word in May 1948.

“The way I provided the name was to think of what the device did. And at that time, it was supposed to be the dual of the vacuum tube. The vacuum tube had transconductance, and so the transistor would have transresistance. And the name should fit in with the names of other devices, such as varistor and thermistor. So I suggested the name transistor,” Pierce said during a 1999 interview for PBS.

The world learned of the transistor when announced during a press conference June 30, 1948.

US Patent 2,524,035 for Three-electrode Circuit Element Utilizing Semiconductive Materials (transistor) was granted Oct. 3, 1950, to John Bardeen et al. (and others). You can see it at https://bit.ly/3nmtglg.

By 1952, the transistor was being used in Bell Telephone equipment.

The Indianapolis News newspaper ran an article Oct. 18, 1954, about a local company that would begin manufacturing “the first pocket-sized transistor radio using the amazing transistor instead of conventional vacuum tubes.”

“We are particularly proud to announce production of the new Regency transistor radio at this time,” the article quoted Edward C. Tudor, president of Industrial Development Engineering Associates (IDEA) located in Indianapolis, IN.

The Regency transistor radio was designed and developed by Texas Instruments, Inc., which began operations in 1951 out of Dallas, TX.

Regency, a division of IDEA, commenced manufacturing the transistor radio just in time for the holidays.

The newspaper article described the new Regency TR-1 radio as “slightly larger than a pack of king-size cigarettes.” It weighs 12 ounces, is 5 inches tall, 32 inches wide, and 1.25 inches thick.

The Regency transistor radio uses a flat, round 22.5-volt carbon-zinc battery to provide power for 20 hours of use.

Public newspaper advertisements in November 1954 for the first commercial transistor radio, the Regency TR-1, began. It sold for $49.95 ($509.36 in today’s dollars) and came in four colors; black, bone white, cloud gray, and mandarin red. Later colors added included mahogany and forest green. Some models were manufactured using clear plastic cases.

In 1956, Bardeen, Brattain, and Shockley won the Nobel Prize in physics “for their researches on semiconductors and their discovery of the transistor effect.”

PBS aired the documentary, “Transistorized!” hosted by Ira Flatow, Sept. 1, 1999. It can be seen using this link: https://to.pbs.org/3vIaOam.

A 1955 film documentary shows Regency TR-1 transistor radios assembled at the IDEA Regency manufacturing plant. You can watch it at https://bit.ly/3b60bVs.

Walter H. Brattain earned a Ph. D from the University of Minnesota in 1929. He passed away Oct. 13, 1987, at age 85.

In 1963, William B. Shockley was awarded an honorary Doctor of Science from Gustavus Adolphus College in St. Peter, MN. He passed away Aug. 12, 1989, at age 79.

John Bardeen worked as a theoretical physicist at the University of Minnesota until World War II began. He died Jan. 30, 1991, age 82.

John R. Pierce died April 2, 2002, at the age of 92.

The transistor is responsible for the evolution of electronic device miniaturization, and is perhaps the most important invention of the 20th century.

























Regency TR-1 with cover removed

Regency TR-1 (1954)