The wonders of electronics

Electronics is a young science. It belongs to the, twentieth century, although many of its mathematical aspects were worked out in the latter part of the nineteenth century by such great physicists as Clerk Maxwell and Gauss.

In fact, electronics is not so much a new subject as a new way of looking at electricity. All electrical effects are really electronic because all electric currents result from the movements of electrons, and all electric charges are due to the accumulation of electrons.

Electronics really began when the valve (an evacuated vessel with electrodes through which a current can pass by electronic or ionic flow) was invented, and is concerned with electrons which are free in so far as, they are not limited to solid wires or conductors.

The application of electronics to everyday life, and in­dustry has increased enormously in the last few years. Electronics is a subject which has grown from the physical laboratory to a field so vast that many of its sub-divisions could almost be regarded as separate sciences.

Science, in the last decade has given the machines mechan­ical senses with which they can see, hear, touch, and even "sense" smell. They can combine these senses in their mecha­nical brains, to remember, measure, count and talk. They can do all these things with the greatest accuracy, a millionth-of-a-second speed, far beyond the ability of human beings.

The thing that has made the machine to a certain extent human is the electron.

We cannot, tell exactly what an electron is or what it is like for the good reason that it is far too small to see with even the most powerful microscope. It is one of the smallest par tides in the universe and may be regarded as a tiny piece of negative electricity. We can only observe the effect it produces under given conditions and learn from this its gener­al properties. Much of our information about an electron has been derived from the study of a large group or stream of electrons.

Electrons can see in the dark. They can see things that for centuries have been hidden from man's eyes.

Electrons can hear a fly and make it sound like a modern jet plane taking off.

They can smell "smoke and warn of a fire.

Electrons can "feel" the thickness of the paint on an auto­mobile body, feel temperatures and control the operation of furnaces.

They can remember what someone told them a month or a year ago. Electrons can even make you see yourself think, by measuring the faint current generated in our brain and making a visible graph, which will tell whether you have actually added a column of figures, or just looked at them.

Electrons are also high-speed calculators. They calculate instantly where it would take mathematicians hours or days.

How can the electron, so small that it takes 30 billion billion billion of them to weigh 28.3 gr, create these wonderful things?

In all matter electrons are infinitesimal negatively charged particles that whirl at lightning speeds around the cores of atoms, like planets around a sun. In that state they work none of the wonders we have described.

To put them to work they must be set free from various substances in one of three ways — by heat; by the action of light; and by bombardment or collision with other electrons.

Here we shall discuss the first two ways — the third one will be described in the articles to follow.

A source of electrons is enclosed in a vacuum tube. The source, usually a metal filament, emits electrons from its surface when heated. Electron tubes give these electrons a place to move about. A positively charged plate is provided to attract them. Suspended in this electron stream between filament and plate is a mesh-like grid that regulates the electron flow.

Since electrons can move freely through a vacuum, electricity is at last freed from the wires, pipes and cables. We can reach inside a vacuum tube, liberate electrons from their atoms, control their actions by infinitely varied elements placed inside the tube, and thus make them "perform the impossible".

A wonderful thing about electrons is that they enable us to control or amplify any sort of wave motion. That means more than it seems to. Your own ears and eyes detect only certain wavelengths as sound or light. The rest of wavelengths are easily detected by electron tubes. Thus the electron carries us into a vast unexplored world which we cannot see, hear, or feel, and brings it to our senses.

The most widely known piece of electronic apparatus in which the electrons are set free by the action of heat is the valve. It can be small or 25 feet tall. In the past the streams of electrons in valves were used only to receive and amplify wireless signals. But as people began to realize that electronic streams could do more than that, electronic vacuum tubes began to be used in many ways quite unconnected with wireless.

Electronic instruments, such as radar, can detect airplanes a hundred miles away, count them, tell their speed and direction. They can see in the dark, and detect submarines under the sea.

Electron tubes make the movies talk. Other electron tubes can see "black light"—infra-red radiation given off by all warm bodies. Thus they can feel, record and control temperature.

Coloured television is entirely an electronic wonder. In television an electric beam strikes a fluorescent screen with such speed, that the eye blends them into a solid picture.

In the electron microscope, streams of electrons are bent magnetically in much the same ways that light waves are focused by glass lenses. Electrons are vastly smaller than light waves and hence can be used to magnify objects up to 100,000 times.

Electronic prospecting for oil and minerals is widely used all over the world. Miniature broadcasting stations send waves deep into the earth, to report in electronic lan­guage: "There is some kind of mineral 600 feet down". Intentional explosions shaking the earth and sending back waves whose shapes are recorded electrically, say "Drill here and you should find oil fields".

All of these, and thousands of other applications, are al­ready in use.

A device in which electrons are set free by the action of light is the phototube. A phototube or "electric eye" sees because electrons are liberated when light strikes certain substances within the tube. It is, in fact, a two electrode valve, with its cathode replaced by a cathode of ceasium or some other material which emits a stream of electrons when exposed to light.

In conventional light-meters used by photographers light striking cells generates its own power direct from sun­light. Electrical energy direct from sunlight! This result is obtained by the freeing of electrons. As knowledge increases we may see the day when all the energy needed to run a household comes from sunlight releasing electrons from special metal plates built into the roof.

What else does the future hold in store for us in new electronic developments? The research laboratories are working constantly to produce a wall screen to replace our pres­ent television tube. The videotelephone, by which one may see the person to whom he is speaking has already been developed. This may soon be put into general use.

Many new developments are possible with the use of radar. One of these is the automatic control of automobiles on highways. We may one day see automobiles travelling safely along roads steered solely by means of radar.

The construction of manned space ships that can travel to other planets is now being studied. When the time comes for these space ships to be built, electronics will play a most important part in their operation.