How Computers Began II

 How Computers Began

But that was only the first problem. The second was the heat developed by such computers. "ENIAC" consumed a lot of current, and most of it was convelled by the tubes into completely undesirable warmth. With its 150,000 watts, the apparatus had the heating power of fifty domestic heaters. It was not only the technicians and mathematicians who suffered in consequence; the effects were even worse on the many thousands of electrical condensers, whose insulating materials simply melted away.

By that time a considerable number of vacuum tube computers had been built, but it began to look as if electronic computing, which had commenced its career with such a burst of optimism, was already at the end of its tether, for the simnple reason that vacuum tubes get hot and burn out.

Then, just at the right time, "transistors" were invented: small circuit eIements - semi-conductor devices - consisting mainly of a piece of crystal. They can do everything tubes can do, but they use hardly any current and produce practically no heat. Moreover, they last a hundred or a thousand times longer than vacuum tubes.

To top it all, they are often no larger than the head of a match. Perhaps you still remember the old-time radios with gigantic storage batteries which we had in the 1930's. Compare them with the cigarette-pack size beachsqueakers of today and you will reallze what havoc the transistors have caused!

It was at this point that a certain amount of standardization began to be introduced into the world of automatic calculators. Previously, the tubes had been attached as in ordinaly radios to a stable metal chassis, and joined together by a jungle of wires in which even the manufacturers could hardly find their way about. Transistors are assembled differently. They arc placed on postcard-size insulated base-plates, connected by fine wires or by leads formed from vaporized metal on boards made of insulating material, caIled "printed circuits." Spring contacts are attached, and the panels are placed vertically side by side on the back wall of the computer. There they stand like paperbacks in a bookcase, and they can be exchanged, if need be, by hand.

Although transistors are hardly cheaper than tubes (originally they were much dearer), they have made electronic computers cheaper to build, bccause they have standardized construction of them.

New and revolutionary developments are now under way. The transistor combinations are to be replaced by still smaller llne elements called "micromodules." What was once a radio-size tube chassis, and is today a postcard-size plug-in unit, will be no bigger in future than a little tube about the size of a pencil stub (and, like a pencil, six-sided) containing a heap of cardboardthick micromodules. These tiny elements are being used today, but they are still so ferociously expensive that so far they are only being installed in artificial satellites, where every ten-thousandth of a cubic inch counts.

Now we shall begin to concern ourselves in earnest with the way the computers actually work. Before we start, however, we must turn our attention to a field that is still mainly a theoretical one: the theory of information. It is far more interesting than one might suppose.

Information - Counted, Measured and Mailed >>>>

© by PhiloPhax & Lauftext & Redaktion Lohberg
Kybernetik - Was ist das?

First printed in Germany: 1963

 

Cybernetic Computer and Electronic Brain


The fascinating story of how computers work in clear, non-mathematical language