1947

Transistor

Walter Brattain (1902–1987), John Bardeen (1908–1991)

If we were to travel back in time to 1945 or 1946, we would find a thriving electronics industry in the United States. People were buying radios and television sets. Electronic innovations like radar were revolutionary. And the world’s first real digital computer, known an ENIAC, came into being in 1946. All of these electronic devices were powered by vacuum tubes. But vacuum tubes were a real pain. They were big (about the size of a pill bottle), hot, prone to burning out, expensive, and they used a lot of power. When ENIAC first started operation, its tubes needed to be constantly replaced. There had to be a better way.

The better way started in 1947 with the discovery of the transistor by American scientists John Bardeen and Walter Brattain at AT&T’s Bell Labs. It then became reality in 1953 and 1954 when the first germanium and then silicon transistors began mass production.

A typical transistor in this era was a small three-wire device about the size of a pea. A transistor can do two different things depending on the design. It can act as an on-off switch, which is how transistors are used in computers. Or it can act as an amplifier, which is how transistors are used in radios and televisions. Transistors are small, lightweight, reliable, efficient, and (eventually) incredibly inexpensive. Engineers immediately started replacing vacuum tubes with transistors.

One of the first transistorized devices to appear in the marketplace was the transistor radio in 1954. Transistor radios were small, portable devices that could run off of a 9-volt battery and fit in a pocket. With mass production they were incredibly inexpensive. People had never seen anything like them, and billions of transistor radios were sold. The portable music craze had begun.

Also in 1954, the first transistor computer, TRADIC, came online. Compared to a vacuum-tube machine it was tiny and used only 100 watts. This meant that the computer could fly in an airplane—something that would have been impossible with vacuum tubes.

Transistors would eventually allow engineers to develop thousands of new devices. They gave engineers amazing freedom compared to the technology they replaced.

SEE ALSO Radio Station (1920), Color Television (1939), Radar (1940).

This is an early transistor used in the IBM 1401.