Radio Broadcast (May-Oct 1922)

THE ROMANCE OF THE RADIO TELEPHONE Being the Story of a Laboratory Toy Which Fell Prey to Unscrupulous Stock Promoters, Became a Scientific Farce, Was Taken Over by Its Supposed Rival, and Turned into a Real Success By C. AUSTIN THE story of the radio telephone is a study of extremes. It is the most popular fad at this moment, yet only a short while ago it was the most unpopular invention ever .introduced to the public. To-day it is in many good hands for full and sound exploitation; a dozen years ago the wireless telephone, as it was then called, was the prey of unscrupulous stock promoters who used it as a means of prying money away from a gullible public. In its present state of development, it is a partner of the wire telephone; in its pioneer days it was supposed to be a mortal enemy of the wire telephone, and not a few among laity and technicians alike were ready to sound the death knell of the less spectacular wire telephone. THE HANDICAP OF BEING MARVELOU-S ' WHAT could be more startling than the idea of talking through space? Imagine a simple device which, at a stroke, could render the present maze of wires, that connects the telephones of the nation into one complete network, more or less obsolete? Consider for a moment the wireless telephone which could be carried about in one's vest pocket and which, at any desired moment, would enable us to speak with some distant person with no other formality than the opening up of a simple loop of wire! Even in the light of the present radio telephone success, such suggestions appeal to the imagination and sound possible; yet the truth of the matter is that while we can talk through space, the radio telephone has very definite limitations which prevent its taking the place of the present wire telephone. However, some dozen years ago these word pictures were handed about to a credulous public who were ever ready to place their money in what appeared to them to be a second Bell telephone opportunity. Most inventions, especially if they are of the highly complicated nature of the radio telephone, must spend a long period of incubation in the laboratory, under the constant nursing of a corps of inventors and technicians. Originally, the radio telephone was in good hands — in the hands of serious electrical engineers who had discovered the peculiar action of an electric carbon arc when connected with a few turns of wire and what is known as a condenser. A condenser is simply two electrical conducting surfaces, separated by a non-conductor. These conductors absorb and hold an electrical charge; but when the charge becomes too great, the condenser lets go, just as a rubber band which has been pulled to its utmost point and beyond finally snaps and lets go, giving off all the power which has been stored up during the stretching process. An electric carbon arc, when connected with a few turns of wire and a condenser, sets up a vibrating current, so to speak, in the circuit containing the arc, coil of wire, and the condenser. The electrical engineer calls this vibrating current a high-frequency current. Alternating current, which is used to such a large extent for lighting and power purposes, is also a vibrating current, in that it flows first in one direction, and then in the other, changing its direction of flow sixty times per second in the usual power supply line. Now, when vibrating currents of sufficient frequency are obtained, it is possible to propagate a portion of these currents through space in the form of invisible radio waves. A system of elevated wires, known as the aerial or antenna, and a connection with the ground serve to impart the waves to the air. At some distant point another system of elevated wires known as the antenna, as well as a ground connection, serves to gather an infinitesimal portion of the radio waves which have been extending in all directions, and to lead them to the receiving