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UNITED STATES EARLY RADIO HISTORY
THOMAS H. WHITE | |
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Pre-War Vacuum-tube Transmitter Development (1914-1917)
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AT&T initially developed vacuum-tubes as amplifiers for long-distance telephone lines. However, this was only the beginning of the device's versatility, as various scientists and inventors would develop numerous innovations, including efficient continuous-wave transmitters, which would eventually replace the earlier spark, arc, and alternator varieties. LEE DEFOREST In 1914, the first vacuum-tube radio transmitters began to appear, a key technical development which would lead to the introduction of widespread broadcasting. Both amateurs and commercial firms started to experiment with the new vacuum-tube transmitters, employing them for a variety of purposes. One of the first persons to adopt the new technology was Lee DeForest. Six years after suspending his efforts to make audio transmissions, when he had unsuccessfully tried to use arc-transmitters, DeForest again took up developing radio to transmit sounds, including broadcasting news and entertainment, this time with much more success. (In retrospect, DeForest recognized the irony that he had overlooked the potential of developing his Audion as a radio transmitter. Reviewing his earlier arc-transmitter efforts, he wrote in his autobiography that he had been "totally unaware of the fact that in the little audion tube, which I was then using only as a radio detector, lay dormant the principle of oscillation which, had I but realized it, would have caused me to unceremoniously dump into the ash can all of the fine arc mechanisms which I had ever constructed, a procedure which a few years later actually took place all over the world!") Radiotelephony For Railroads, from the May 30, 1914 Electrical World, reported a test installation by the DeForest Radio Telephone & Telegraph Company on a Delaware, Lackawanna & Western Railroad train, designed for internal company communication, while High-Frequency Oscillating Transmitter for Wireless Telephony from the July 18, 1914 Electrical World reviewed a DeForest transmitter with which "it is possible to telephone one to three miles, and the device is well adapted for use on small yachts, tugs, ferryboats, etc." DeForest later expanded into broadcasting activities, eventually inaugurating nightly transmissions from his experimental radio station, 2XG, located in the Highbridge section of New York City. Wireless Transmission of News, which appeared in the December 30, 1916 issue of Telephony, covered the start of the broadcasts, which were declared to be "a remarkable step forward in the distribution of the world's news and music" and additional reports included Dance to Wireless Music 40 Miles Off from the December 31, 1916, New York Times, and Election Returns Flashed by Radio to 7,000 Amateurs in the January, 1917 issue of The Electrical Experimenter. Beginning in early 1917, QST magazine carried a series of reports about 2XG's nightly broadcasts -- included in these Highbridge station reports was a note that DeForest was investigating creating "a sort of wireless newspaper to which every amateur with an instrument can subscribe", plus speculation by QST about the possibilities of using radio for advertising. AMERICAN TELEPHONE AND TELEGRAPH COMPANY Meanwhile, in June, 1915 the American Telephone & Telegraph Company and its Western Electric subsidiary installed a powerful experimental vacuum-tube transmitter at NAA, the U.S. Navy station located in Arlington, Virginia, across the Potomac River from the U.S. capital. It quickly achieved remarkable distances for its audio transmissions, as reported by Wireless Telephony Now From Washington to Honolulu, in the November, 1915 issue of The Electrical Experimenter, and By Wireless 'Phone from Arlington to Paris, which appeared in the next month's issue. The NAA tests, which marked the beginning of a ten-year period of increasing prominence for AT&T within the U.S. radio industry, led Paul Calhoun to ask Why Not Have the President Talk Simultaneously to "All the People?" in the September, 1916 issue of The Electrical Experimenter. Fleet Tests Radio Phone from the January 31, 1916 New York Times reviewed U.S. Navy tests of radiotelephone equipment supplied by AT&T. MARCONI The Marconi companies joined those experimenting with the new vacuum-tube transmitters, and in the September 5, 1914 Electrical World, Wireless Telephone Set announced that "A radio-telephone set which is designed for an oversea working range of 50 km (31 miles) between ship aerials 100 ft. high and having 200-ft. spans is being placed on the market by the Marconi Wireless Telegraph Company". In the April, 1915 issue of The Wireless Age, Marconi's Wireless Telephone was a further report on the low-powered vacuum-tube transmitter, while a test transmission, fom the American Marconi plant at Aldine, New Jersey to David Sarnoff aboard the Bunker Hill off the coast of New York, was reported in Waft Music Into Air By Wireless from the June 12, 1916 New York Times and Marconi Wireless Telephone from the August, 1916 QST. Although the details are somewhat murky, there is evidence that Sarnoff -- at the time a mid-level American Marconi employee in New York City, but who, thirteen years later, would become the third president of the Radio Corporation of America -- was particularly influenced by DeForest's groundbreaking broadcasts in 1916. Sarnoff's famous "Radio Music Box" memo, circa November, 1916 -- there is some uncertainty about the date -- reviewed the possibilities of his company setting up a radio broadcast service aimed at the general public. Sarnoff's memo didn't mention DeForest, however, one of Sarnoff's biographers, Carl Dreher in An American Success, believed that the 2XG broadcasts were its main inspiration. (There is an interesting reference near the beginning of this memo about the "failure" of earlier attempts to distribute audio programming "by wire". This may be a reference to the Newark Telephone Herald, which had gone bankrupt in 1912. However, as of 1916, the Budapest Telefon Hirmondó and London Electrophone had both been in operation for more than twenty years, so this statement wasn't universally accurate.) Assuming the "Radio Music Box" memo actually does date to November, 1916, it is probably fortunate that the Marconi management didn't try to start up a broadcast service at that time. Just five months later, with the entrance of the United States into World War One, a complete ban on all radio listening by private citizens would take effect, so the new service would have been shut down just as it was beginning to go into operation. OTHER EXPERIMENTERS Although DeForest's experimental broadcasts are the best known, other experimenters, not as well publicized, were also on the air using vacuum-tube transmitters. For example, in 1915 Harold Power founded the American Radio and Research Corporation (AMRAD) in Medford Hillside, Massachusetts, which also began broadcasting over its experimental station, 1XE. On March 18, 1916, Power transmitted a widely heard musical concert, intended to impress financier J. P. Morgan aboard the S.S. Philadelphia, which was reported by Music Sent By The Wireless in the March 27, 1916 Boston Globe. Later reports included Wireless Achievements at Tufts College in Massachusetts, which appeared in the April 16, 1916 Electrical Review and Western Electrician, and Tufts College Sends Music by Radio from the February, 1917 The Electrical Experimenter, while Dawn of Radio, from Radio Digest, gives a broader history of this groundbreaking station. Meanwhile, in the June, 1916 issue of The Electrical Experimenter, Albert Marple reported that "there is a new 'fad' in Southern California", as Earl C. Hanson transmitted entertainment to his neighbors in Wireless Music With Your Meals. Music By Wireless from the August, 1917 The Electrical Experimenter reported that a shipboard concert on a vessel traveling from Hawaii to Russia had been heard by listeners in a wide radius of the Pacific Ocean. However, all of these fledgling broadcasting experiments came to an abrupt end on April 6, 1917, when the United States entered World War One. At that time, all radio stations not needed by the government were closed, and it became illegal, for the duration of the war, for the general population to listen to any radio transmissions, from any source. |
| "Meanwhile, demonstrations had been given to officers of the United States Navy, including Captain (later Rear Admiral) W. H. G. Bullard. It was the generous coõperation of such open-minded officials as Bullard and Colonel Reber, a personal friend of Carty, that later made it possible to attempt the more pretentious program of transmitting speech across the Atlantic. But in the early stages of his contact with these Bell System engineers, Bullard was far from being enthusiastic. Writes R. A. Heising, in his reminiscences: 'Captain Bullard told me late that year that he had no faith in our being able to talk across the Atlantic when the subject was first broached to him. He felt it was the idea of people who knew nothing of radio. He didn't expect telephone people, of all people, to be able to do it. It was only the fact that the engineers who approached him had unquestioned reputations in the engineering world that prevented him from throwing them out and dismissing the proposal from his mind. He therefore listened politely to what they had to say, and witnessed the tests without being convinced. They seemed to be so enthusiastic about the project, however, that he finally thought that as it was their own money they wanted to spend, they should be given whatever opportunity there was, and he would look into the matter further.'"--"Pioneering in Radio Telephony", Bell Telephone Magazine, February, 1941. |