Author: technicshistory

The crucible of war prepared the ground for the transistor. The state of technical knowledge about semiconductor devices advanced enormously from 1939 to 1945. There was one simple reason: radar. The single most important technology of the war, its applications included detecting incoming air raids, locating submarines, guiding nightfighters to their targets, and aiming anti-aircraft… Continue reading The Transistor, Part 2: Out Of The Crucible →

The road to a solid-state switch was a long and complex one. It began with the discovery that certain materials behaved oddly with respect to electricity - differently than any existing theory said they ought to. What followed is a story that reveals the "scienceification" and "instutionalization" of technology in the twentieth century. Dilettantes, amateurs… Continue reading The Transistor, Part 1: Groping in the Dark →

We have now recounted, in succession, each of the first three attempts to build a digital, electronic computer: The Atanasoff-Berry Computer (ABC) conceived by John Atanasoff, the British Colossus projected headed by Tommy Flowers, and the ENIAC built at the University of Pennsylvania's Moore School. All three projects were effectively independent creations. Though John Mauchly, the motive force… Continue reading The Electronic Computers, Part 4: The Electronic Revolution →

The second electronic computing project to emerge from the war, like Colossus, required many minds (and hands) to bring it to fruition. But, also like Colossus, it would have never come about but for one man's fascination with electronics. In this case, the man's name was John Mauchly. Mauchly's story intertwines in curious (and, to… Continue reading The Electronic Computers, Part 3: ENIAC →

In 1938 the head of the British Secret Intelligence Service quietly bought up a sixty acre estate fifty miles from London. Located at the junction of railways running up from London to parts north and from Oxford in the west to Cambridge in the east, it was an ideal site for an organization that needed… Continue reading The Electronic Computers, Part 2: Colossus →

As we saw in the last installment, the search by radio and telephone engineers for more powerful amplifiers opened a new technological vista that quickly acquired the name electronics. An electronic amplifier could easily be converted into a digital switch, but one with vastly greater speed than its electro-mechanical cousin, the telephone relay. Due to its… Continue reading The Electronic Computers, Part 1: Prologue →

We saw last time how the first generation of digital computers were built around the first generation of automatic electrical switch, the electromagnetic relay. But by the time those computers were built, another digital switch was already waiting in the wings. Whereas the relay was an electromechanical device (because it used electricity to control a mechanical… Continue reading The Electronic Age →

Our previous installment described the rise of automatic telephone switches, and of the complex relay circuits to control them. Now we shall see how scientists and engineers  developed such relay circuits into the first, lost, generation of digital computers. The Relay at Zenith Recall to mind the relay, based on the simple idea that an electromagnet could operate a… Continue reading Lost Generation: The Relay Computers →

The first telephones [Previous Part] were point-to-point devices, connecting a single pair of stations. As early as 1877, however, Alexander Graham Bell envisioned a grand, interconnected system. Bell wrote in a prospectus for potential inventors that, just as municipal gas and water systems connected homes and offices throughout major cities to central distribution centers,1 ...it is conceivable that cables… Continue reading Only Connect →

[Previous Part] The telephone was an accident. Whereas the telegraph networks of the 1840s emerged out of a century-long search for the means to communicate by electricity, men only stumbled over the telephone while searching for a better telegraph. For this reason, it is easier to pin down a plausible, though not incontrovertible, date for the invention of the… Continue reading The Speaking Telegraph →

[Previous Part] In 1837, American scientist and teacher Joseph Henry took his first tour of Europe. During his visit to London, he made a point of visiting a man he greatly admired, the mathematician Charles Babbage. Accompanying Henry were his friend Alexander Bache, and his new acquaintance and fellow experimenter in telegraphy, Charles Wheatstone. Babbage told his… Continue reading The Relay →

In our last installment, we saw how the component parts that could be used to build an electromagnetic telegraph came into being. Now let us see how they were put together. The Time Ripens By the 1830s, the time was ripe for the development of the telegraph on a large scale. In the U.S. and Britain, the age… Continue reading The Entrepreneurs →

We last left the electric telegraph wandering through the decades in a kind of limbo. A fascinating demonstration piece, a promising curiosity, it had yet to prove itself as a practical instrument. By 1830, however, electricians had made several crucial new discoveries that made the electric telegraph as we know it possible. It began with a frog.… Continue reading Galvanism →

To begin our story of the switch, we must seek the origins of the electric telegraph. From this device arose the telecommunications industry, which, in turn, was the wellspring of digital computing as we know it.  It came about only after many efforts over nearly a century to convey intelligence (intelligence meaning roughly what we mean by information) by electricity. One important… Continue reading An Expeditious Method of Conveying Intelligence →