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It's an interesting incontrovertible fact that the new South San Francisco station, geared up for an everyday business with Honolulu in addition to inland points, uses just one thirtieth of the electric power needed to operate the spark system between the coast of Newfoundland and Ireland, which is about four hundred miles the shorter distance. The prospects of the Poulsen system were early seen by C. F. Elwell, a Stanford graduate who had specialized on wireless issues. Mr. Elwell, as long as two years in the past, carried on wireless conversations from Stockton to Sacramento, a distance of 50 miles overland, and his dialog was overheard at Palo Alto, 85 miles away. In the primary place there are the two masts, at the present time the tallest on the earth. At current messages are carried into Chicago by means of the smaller and therefore much less efficient stations of El Paso and Fort Worth. Yet there are other disturbances fairly as serious. There are other curious happenings of a milder variety and never much less romantic. These poles are about the only factor about the place that the uninformed outsider can mentally grasp. The subsequent factor to puzzle the wits of the outsider are the copper coils fastened to the ceiling of the room.

But the outcomes achieved by the Federal folks prove that distance above sea level has nothing to do with the case--which is quite a unique factor from saying that peak above the floor of the bottom shouldn't be an advantage, for it's a decided one. This generator is about an important thing in the shop. To borrow another Veeder illustration, if a pistol (which represents the spark impulse) is fired close to an open piano, all the strings are set in vibration; but when a tuning fork be struck, which gives off sound waves of equal size (comparable to those of the Poulsen generator), then only the strings attuned to that be aware give out a response. The movements of the wire thus seem on its length as a zigzagging white line. The tape comes prepared with a central line of small holes, the dash or the dot being punched on its respective aspect of this line. Masts of the dimensions just in-built new South San Francisco station will soon be positioned in a direct line from right here to New York.

But meantime the Honolulu operator took messages from San Francisco with none interruption, which proves the steadiness of the Poulsen waves. But this did not fully prove the efficacy of the Poulsen system overland, insulated copper cable since San Francisco is by the sea and Los Angeles also near it. On account of its "high frequency," the use of the telephone beneath the Poulsen system is as limitless as telegraphy itself. The sending price by the spark system is from 15 to 20 words a minute. Poulsen hand despatched and the ocean cable run from 25 to 30. The rate of sending and receiving has thus its human limitations. The waves passing over the antenna run into a whole bunch of hundreds the second. Between their tips is stretched seven miles of delicate wire feelers, known as the antenna, which provides off and receives the electro-magnetic waves of the Morse code. This contrivance knocks out from 200,000 to 1,000,000 long, common waves to the second. These wheels are insulated, besides from copper strips set in at regular intervals. The small pins in turn release larger pins, which operate a set of brushes, throwing the present to one of three revolving wheels. The duplexer, a tough wanting machine for the delicate work in hand, is a pair of wheels driven collectively by a belt from a motor and touched by copper brushes.

It's an iron box sitting above a pair of large magnetic coils. Contained in the box are a couple of massive carbon rods set a small area apart, end to end. This sensitised paper, hid in a field, is fed as tape from a roll and passes in front of a small hole opposite the lenses. Instead of waiting for the wires to clear, the operator sits in entrance of a punching machine feeding from a roll of tape. Before tape is either despatched or acquired, preparations are made between stations by the peculiar key and receiver. One night time the island operator distinctly caught spark messages sent by certainly one of the big trans-pacific liners leaving Japan. That is why some wireless systems nonetheless work solely at night. Finally got here the eventful evening when the new Federal station at Honolulu was in a position to talk for itself. Then got here a lapse, and nothing, was again picked up till the vessel was near Honolulu.