Radio operator

“ 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. ”

“ They walked out to the radio shack. And there Jack launched into an enthusiastic description of his work. He was seeking, he said, to work out some of the fundamental problems demanding solution as a result of the tremendous increase in both broadcasting stations and receivers.
“There are six or seven such problems,” he said. “First, we must have a radio receiver which will provide super-selectivity—a receiver which will enable the Operator to select any station he wants to hear, whether or not local stations are operating. Such selectivity must go to the theoretical limits of the science. ”

“ Still, it is your job and you expect to put it first and fit your own affairs in around it. Besides, you get used to the regularity of the hours and soon do not notice the monotony of the rules. You can readily understand why, at all official radio stations, somebody must always be on the watch for S O S calls. On shipboard there are three classes of wireless stations: those having continual service with an operator who always has his ear to the receiver while the ship is in motion; those where the office is open only at stated hours and an operator listening merely for a limited time ”

“ The few that might furnish information were studied carefully but in a majority of cases the description of the plane which the sender of the message had seen failed to come close to that of the machine they sought.
Timms found several messages which appeared worth telephone calls to the senders but on each occasion he was doomed to disappointment.
“I thought you said we’d have some definite news before midnight,” he told Bert.
“There’s nearly two more hours,” replied the radio operator hopefully. “I won’t concede defeat until the last minute.” ”

“ He cleared his throat and looked around with his well-known lecture-room air.
“Now that the author of the strange phenomena which have confronted us in this house has been apprehended,” he said, “explanations, and such further investigations as are needed to completely clear up the mystery, are in order.
“You are all aware that the manifestations we have witnessed were under the control of an operator established in an old farmhouse eight miles west of here, and that the mechanism he used was a powerful and complicated radio set. ”

“ At night we use those lights or blinkers and make ’em wink by electricity. It’s really sending wireless messages with lights instead of sound waves.”
“And how does a fellow become a first-class radio man?”
“To become a first-class man, you’d have to have a good knowledge of all parts of the ship, and all radio laws and regulations and general radio procedure. You could take your examination nine months after you entered the service, but there are mighty few radio men who are ready to take it so soon.”
“What about Mr. Sharp here? He is chief electrician. ”

“ Antenna construction is limited only by imagination. There are many types and configurations. However, the operator must be careful not to construct an antenna that has a high standing wave ratio, which can damage radio equipment. Standing wave ratio meters should be used when testing or using unfamiliar antennas. In selecting an antenna for an HF circuit, the operator must know the type of propagation.
(1) Ground-wave propagation requires low takeoff angles and vertically polarized antennas. The whip antenna provides good omnidirectional ground-wave radiation. ”

“ 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. ”

“ In that way, a single pair of wires can be used for transmitting, simultaneously and without any interference, several different telephone conversations. It takes very much less power than would radio transmission and the conversations are secret. The ordinary telephone conversation can go on at the same time without any interference with those which are being carried by the modulations in high-frequency currents. ”

“ Millions of messages going in all directions, crossing and recrossing one another, as is done every day by wire, are probably an impossibility by wireless telephony. Weird and little-understood conditions of the ether, static electricity, radio disturbances, make wireless work uncertain, and such a thing as twenty-four-hour service, seven days in the week, can probably never be guaranteed. In radio communication all must use a common medium, and as its use increases, so also do the difficulties. The privacy of the wire is also lacking with the wireless telephone. ”

“ 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. ”

“ The lack of know-how and equipment may keep many from the air, but only a tiny fraction of those with resources and intelligence can hope to communicate by radio at the same time if intelligible communication is to be had, even if the entire radio spectrum is utilized in the present state of commercially acceptable technology. ”

“ 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. ”

“ 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. ”

“ Although a war invention, its peacetime service will be to save lives. It is a very simple matter to rig up a wireless-telegraph system that will send messages to a considerable distance, and simpler still to rig up a receiving-set. European governments have always discouraged amateur radiotelegraphy, but in this country restrictions used to be so slight that almost any one could set up and use a radio set, both for receiving and for transmitting. ”

“ Applicant shall show that there is installed in each aircraft a type certificated radio antenna system, which has for its purpose the collection of radio range signals, weather broadcast and emergency messages transmitted within the frequency range of 200 to 400 kilocycles. The design of this antenna system shall be such as to eliminate insofar as possible, consistent with the advancement of the art, that type of interference commonly known as rain, snow, sleet, or dust static. ”

“ And now came the great test for her manifold radio equipment. There was no time to lose. Signals must be sent to all battleships within range to support her by diverting their fire to these fast and powerful ships; signals must be sent to all available destroyers to harass them with torpedo attacks; and still the direction of the fleet as a unit must go on, and all without mutual interference of messages. Signals were flashing out simultaneously on different wave-lengths from three or four separate antennæ, both by radio telephone and by radio telegraph. ”

“ Don unwrapped something that looked like a flat cigarette case with two appendages, one a disk of perforated hard rubber the size of a half dollar, and the other a three-quarter-inch-wide ribbon of opaque plastic. "I've got it, sir."
"Good. What you see is a highly advanced radio transmitter and receiver. You can imagine its value in the field. It's a pilot model you were bringing back from the contractor for tests here. ”

“ Truly the science of radio-telegraphy has made rapid strides since the days of the “coherer,” until now, after the war, it is the most advanced in our human civilisation, and at the same time full of romance. Not a month passes but something new is discovered in that high-built, well-knit laboratory, where daily the keenest brains of wireless experimenters are at work devising, testing, and too often scrapping new instruments, new circuits, and new devices in order to improve and render less complicated both the ordinary wireless by Morse, and that modern marvel, the wireless telephone. ”

“ Just the same, only in radio telephony we are confronted by a problem not met with in wireless telegraphy. We have not only to transmit sound, such as isolated dots and dashes, but to send through the air every rise and fall and inflection of the human voice just as it is recorded in the minute lines of a phonographic record. ”

“ We'll try to contact phone stations wherever possible for this program we have in mind. Most of the stuff will be put on tape, and Dad will probably want you to prepare typed copies, too. You can do enough to take a big load off the rest of us."
"I'll be happy to try."
They spent the rest of the day in the radio room of the science shack. Ken taught Maria the simple operations of turning on the transmitter and receiver, of handling the tuning controls, and the proper procedure for making and receiving calls. ”

“ The reason that distant radio stations are sometimes heard better than nearby ones, is because the other waves are propagated both in an upward and an outward direction. The more or less parallel waves reach nearby stations, while those going upward are deflected downward at an angle upon reaching the upper strata, and arrive at a spot on the earth's surface far beyond the normal range of the station. Ships which are, therefore, at that particular spot at a given time are enabled to receive the signals. ”

“ Nearly all the big wireless companies have great stations fitted with powerful telephone transmitters and at given hours of the day and night they send out songs by popular singers, dance music by jazz orchestras, fashion talks by and for the ladies, agricultural reports, government weather forecasts and other interesting features. Then by simply shifting the slide on your tuning coil you can often tune-in someone who is sending Morse, that is, messages in the dot and dash code, or, perhaps a friend who has a wireless telephone transmitter and is talking. ”

“ Nowadays, however, you will occasionally see an indoor aerial used in connection with small, low-power outfits. It does away with the masts and outside equipment and frequently serves the same purpose quite satisfactorily. But most persons prefer the older method and for long-distance work it has, up to date proved to be indispensable. Now the antenna has both electrical capacity and inductance, and when connected up with the apparatus a wireless operator can at will cause it to disturb the magnetic fields surrounding the earth. ”

“ CHAPTER THREE THE RADIO AMATEUR MOVEMENT From the turn of the century enthusiastic young men who built their own items of electrical and wireless apparatus were known as "Wireless Experimenters". Many of them were later granted licences for the use of "Wireless Telegraphy for experimental purposes" (in the United Kingdom) by the Postmaster General under the terms of the 1904 Wireless Telegraphy Act. ”

“ 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." ”

“ At present wireless messages are chiefly of service where secrecy is not of such importance as speed; but an enormous number of experiments are being conducted upon beam wireless, directional wireless, and in the combination of the Radio oscillation with some other oscillations such as those of visible or invisible light. By these means secrecy will be obtained when we discover how to use small powers for long distance, but at present Radio is chiefly of value as a time-saver. ”