Radio

“ The parlor was red in the fading light, and the hall beyond the sliding doors was deeply shadowed. In the sewing room, he remembered, in the drawers of the treadle machine the radio was captured. The rings and secret manuals of the days when radio had been alive. ”

“ The radio-telephone does not transmit the human voice. It reproduces near the ears of the listener similar motions of the air molecules and hence causes in the ears of the listener the same sensations of sound as if he were listening directly to the speaker. This reproduction takes place almost instantaneously so great is the speed with which the electrical effects travel outward from the sending antenna. If you wish to understand radio-telephony you must know something of the mechanism by which the voice is produced and something of the peculiar or characteristic properties of voice sounds. ”

“ Perhaps the next time the radio set begins to howl as if a dozen cat fights were mewling inside of the loud speaker, it is not static that is interfering with the reception from the broadcasting station, but a newspaper photograph which is being sent through the air. ”

“ So I’ll say it all in one sentence—the radio is the most wonderful invention ever conceived by the mind of man.”
“You don’t need to prove it to us,” laughed Bob. “It’s simply a miracle, and we become more convinced of that every day. I’m mighty glad I was born in this age of the world.”
The boys crowded around Mr. Harvey as he explained to Larry and Tim in as simple a way as possible the radio apparatus of the station. ”

“ From the telephone to radio constituted but another such step, and we are now enjoying radio broadcast from stations thousands of miles away. Every time you have an Xray photograph taken you are bombarded, not by rays, but by actual particles that go right through the walls of the tube, which particles are just as real as if they were bullets or bricks, the only difference being that they are smaller. Thus our scientists lead up to the way of sending solids through space. ”

“ That night when I fell off the roof I was running a wire from my room to the aerial on the roof. I’ve been working for a long time with a dear old man who’s a real genius. He invented a special kind of radio and he gave me two of them to try out.”
“I see. That’s what you’re doing now. Did the outside aerial help?”
“Oh, yes, a whole lot. The ‘put-puts’ come in a whole lot more distinctly.”
“The what?” He stared.
“The ‘put-puts’. That’s what we call them. I suppose it’s some special form of code, but it’s not like any I’ve ever heard on the short wave section of our radio.” ”

“ I told him about my visitor and the repair job. "What I did was add a modulator-oscillator-power amplifier, and a few feet of wire for an antenna, coiled around inside the case."
"So what does that make it?"
"Simple. It makes it a radio transmitter. Not only will he hear what the horses are saying, but anyone in town with a radio tuned to that frequency will, too."
"And where does that get you?" The sergeant was still puzzled but not bored now. ”

“ You can see that very few telephone messages can be sent in the long-wave-length part of the radio range and many more, although not very many after all, in the short wave-length part of the radio range. You can also see why it is desirable to keep amateurs in the short wave-length part of the range where more of them can transmit simultaneously without interfering with each other or with commercial radio stations. ”

“ When a sub is heard and located, the listeners call the net-layers by radio, and they go to the spot at a thirty-knot speed. As they approach they soon drown out the sound of the sub, but their speed and number enables them to surround the area in which she is known to be, for she won’t have time to go far from where she was last heard. Paying out their nets, they hem her in and keep the ring of nets closed round her till the area is raked with trailing wires and other electromagnetic detectors which will enable the chasers to concentrate their depth charges with the certainty of a kill. ”

“ Radio is certainly getting to be a country-wide craze. Only the other day I was at one of the big broadcasting stations, and the manager told me that they were actually having trouble to get performers, there is such a demand for them. They seem to be especially hard up for novelty acts—something out of the ordinary. ”

“ We send sound, music by radio waves across half the world from our broadcasting stations. We send light, pictures, across the world from our television stations. We do that by changing the wave length of the light-vibrations to make them radio vibrations, flashing them out thus over the world, to receivers which alter their wave-lengths again and change them back into light-vibrations. ”

“ Bill explained. "It will be all right in the morning. If you want to listen to the radio, you can use the portable radio directional finder. That always works."
"I want to catch the 5 o'clock news and hear the latest on our satellite," Carol replied. She went to the RDF and switched it on to the standard broadcast channel. "Anyhow, I'd feel better if we could put out a signal. The way we're limping along with water in our gas is no fun. ”

“ There is no reason why the benefits of that service should be confined to the persons gathered within these four walls. There are thousands outside who by the means of radio, that most wonderful invention of the present century, can hear every word of this service just as readily as you who are seated in the pews. ”

“ Where the electric light tube would have contained only the filament, these tubes at which they were looking contained also a plate and a grid—the latter being that magical invention which had worked a complete revolution in the science of radio and had made broadcasting possible. ”

“ Audio radio engineers have been working in the very limited audio-frequency band below, say, ten thousand cycles, whereas the workable range where light instead of sound is employed goes away up to millions of cycles. It is confidently predicted that the next great development in radio is in this area. ”

“ Finally, the ladies withdrew, and Myles Cabot, the radio man, began the first discussion of radio that he had undertaken since his return to Poros.
VIII
BUT WHY RADIO?
Three fields of “magic” were open to him, rifle-fire, aviation, and radio. The opportunity for building a workable airplane among people who knew no metal arts was obviously slight. To make a radio set should be possible, if he could find certain minerals and other natural products, which ought to be available in almost any country. ”

“ Here was the powerful short-wave sending and receiving set, an intermediate wave set for communication with near-by cities and other ships of both air and sea, and a radio direction finder. Within this room, a group of mining scouts was carefully taking apart and putting back together one of the Renaud portables, under the watchful eye of Lee. These men must know their radio mechanism. For when the great dirigible dropped these men for scouting in various parts of the Arctic waste, radio would be their only means of communication with the rest of the party. ”

“ By keying the transmitter tube, meters in the receiver tube were made to read in accordance. Then they had another conclave.
"Nothing brilliant," said Jim. "We could use super-output voice amplifiers and yell halfway across the planet if we didn't have radio. We can radio far better than this cockeyed system of signaling." ”

“ And new means for modulating electric current by changing light values may be expected when the American boy starts to play with this new toy.
There has been a veritable army of engineers engaged in the development of radio as a service to the ear, while relatively few engineers have been developing radio as a service to the eye.
It is believed that the distant electric modulation of light for many purposes will soon become a common phenomena and eventually of inestimable service in science, in engineering, in industry, and in the home. ”

“ Directly behind the house we unwrapped two of the packages. One proved to be a set of surveyor’s instruments which the civil engineer quickly assembled. The other looked very much like a radio set with its loop aerials and dials, although there was no speaker or headphone with it. The radio set was placed on a small folding table, and Mr. Easton sighted from that point, while I acted as roadman and Mr. Brandon as chainman. We measured off a distance of two thousand feet in a straight line along the beach, the doctor following with the other package. ”

“ The remarkable growth of the radio-phone has, of course, been due to the radio broadcasting stations which have been established in all parts of the country, and from which concerts, speeches, market reports, baseball reports, news reports, children's stories and religious services are sent out. ”

“ A little later they stood entranced in the Convention Hall before a new, beautifully modeled radio amplifier, so massive that the volume of music it poured forth actually seemed to cause vibration in the walls of the great room in which they stood.
One of the most interesting features was the radio-controlled automobile. The crowd before this almost incredible invention was so dense that the operator was handicapped in his demonstration.
The car was about seven feet in length, with a cylindrical mass of wire rising about six feet above its body. ”

“ Since 1903, wireless has made possible the radio, the wireless telephone, and now television. Is it not probable that the future holds other great marvels, one day to become commonplace-perhaps in God's Kingdom! ”

“ The radio’s tubes glowed red.
“Say! A radio with its own private wave length is worth a fortune! I know a man high up in Communications. Let me show it to him.”
“Not for worlds.”
“You’ll be rich and famous.”
“No! No! Oh, I wish I hadn’t brought it here. Can’t you see that it was loaned to me by a very dear friend and that he alone can release it?”
“Yes,” he replied soberly. “I won’t breathe a word about it until you give me the sign.”
“Thanks—oh, thanks!” she stammered. “You really had me worried.”
“And now,” he said, “how about having another try at the ‘put-put’ of the gremlins, or subs?” ”

“ To get music by radio, a microphone converts sound into electrical modulation, which, carried by radio to distant places, is then changed back into sound and we hear the music.
To get pictures by radio, a sensitive cell converts light into electrical current, and at radio distances changes these currents back into light values, and one may see the distant scene; for light is the thing of which pictures are made, as music is made of sound. ”

“ RADIATION RESISTANCE—The resistance, which if inserted in place of an antenna, would consume the same amount of power as that radiated by the antenna.
RADIO FREQUENCIES—Electromagnetic frequencies that fall between 3 kilohertz and 300 gigahertz and are used for radio communications.
RADIO HORIZON—The boundary beyond the natural horizon in which radio waves cannot be propagated over the earth’s surface.
RADIO WAVE— (1) A form of radiant energy that can neither be seen nor felt; (2) An electromagnetic wave generated by a transmitter. ”

“ If any of you really want to know how to build a radio set in a practical, get-there way, all you’ll have to do is to get Doctor Field’s consent and come round to our shop in the basement of the school dormitory and we won’t soak you much. ”

“ Herb took him up. “Look at telephone and telegraph and electric lighting systems. There have been changes in them, of course, but beside the rapid-fire changes of radio, they seem to have been standing still.”
“There haven’t been any changes to speak of in the electric lighting systems for the last fifteen 96 years or more,” said Bob. “And the telephone has stayed just about the same, too.”
“There’s no doubt about it,” said Joe. “Radio has got ’em all beat as far as a field for experiment is concerned. Say,” he added fervently, “aren’t you glad you weren’t born a hundred years ago?” ”

“ We raided your room and took therefrom your radio sending and receiving outfit, and have added thereto necessary equipment for erecting an aerial. This we leave with you in order that you may summon help through the atmosphere. Meanwhile, you may comfort yourself with the distinction of being the first college freshman ever given a radio hazing. Now, put up your aerial and send out a message for help. Radio is your only hope. Nobody ever stops at this island and it is impossible for passing vessels to see any signal of distress you may devise. ”

“ What for?” cried Bob.
And, “Yes, what for?” echoed others. Mr. Hampton and Rafaela, who already had been admitted to the secret, alone remained silent.
“There’s a man down there who also has been experimenting on radio,” Jack said, “but along different lines. He is trying to find out the laws controlling radio waves for the transmission of vision. Well, maybe, I didn’t put that just right. But this is what he’s after: He’s trying to evolve a radio device for the broadcasting of scenes. ”

“ Tom wanted to know.
"Because, up to the present, no way has been found of utilizing in radio telephony the entire energy of the electric waves sent out," replied Professor Chadwick. "Only the variations in the waves can be detected, or transformed into sound at the receiving end of a radio telephone system. Therefore an immense amount of electrical energy has to be manufactured in order that the voice vibrations may register their variations as powerfully as possible." ”

“ If you follow directions carefully. And with the new outfit a loop is just as effective an antenna as an outside aerial. They say, too, that to catch broadcasting for not more than twenty-five miles, not even a loop is needed, the circuits themselves acting as the absorbers of energy.”
“I’m going to try it,” declared Jessie, with more confidence. “But I feel that I understand so little about the various forms of radio, after all.”
“You have nothing on me there,” laughed the operator. “I am learning something new all the time. ”