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Arc-Transmitter Development (1904-1928)
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A more compact -- although not quite as refined -- method for generating continuous-wave radio signals was the arc-transmitter, initially developed by Danish inventor Valdemar Poulsen. Because arc-transmitters were less complicated than alternator-transmitters, a majority of the early experimental audio transmissions would use this device.
Valdemar Poulsen -- Lee DeForest -- Federal Telegraph Company -- Charles Herrold and the National Wireless Telephone and Telegraph Company -- United States Navy -- Additional Early Experimenters


Due to their size, complexity and cost, alternator-transmitters were mostly employed for longrange radiotelegraphy, and rarely used for audio transmissions. But another developing continuous-wave technology also showed promise -- the arc-transmitter, which had been perfected beginning in 1902 by Valdemar Poulsen of Denmark. At the 1904 Saint Louis International Electrical Congress, Poulsen submitted a paper reviewing his discoveries, System for Producing Continuous Electric Oscillations, and expressed the hope that this new transmitting system would soon be used for "syntonic wireless telegraphy and telephony". Another Selective Wireless, which appeared in the July, 1906 Electrician and Mechanic, reported on Poulsen's on-going progress, followed by a more detailed review, The Poulsen Wireless Station at Lyngby, from the June, 1908 issue of Modern Electrics. (In addition to his radio inventions, Poulsen was also well known for developing a wire "Telegraphone" sound recording device, reviewed by E. F. Hearns in A Spool of Wire Speaks from the December, 1906 Technical World Magazine). Meanwhile, Wireless Telephony, in the December 8, 1906 Electrical World, reprinted a report from the November 15, 1906 Elektrotechnische Zeitschrift that German experimenter Ernst Ruhmer had successfully employed Poulsen's invention to transmit speech across a laboratory room, which "makes wireless telephony at once possible".

The November 22, 1906 New York Times carried a short announcement, Backs Wireless Invention, that a Lord Armstrong in Great Britain had procured the U.S. rights to Poulsen's patents for $500,000, and a letter to the editor from E. M. Trinks in the June 17, 1907 New-York Daily Tribune, reviewing the potential of the Poulsen system of Wireless Telegraphy, optimistically predicted that there was "every reason to believe that commercial communication will be shortly established between America and Europe". Wireless Over Atlantic, from the July 28, 1907 New York Times also foresaw the imminent establishment of a transatlantic radiotelegraph service, while a report in the December 19, 1907 Philadelphia Inquirer, May Telephone From Ireland to America, further stated "Professor Poulsen said that he hoped to communicate with America, via Ireland, by telephone in February next". This was followed by a couple reviews of Poulsen's predictions about transatlantic radiotelephony in the New York Times: Poulson Confident of Oversea 'Phone, in the December 20, 1907 issue, and Voice Will Carry Across the Sea from January 12, 1908. Finally, a short notice on the front page of the January 1, 1908 New York Times claimed that during the upcoming year, in addition to the radiotelephone service, it would also become possible to send transatlantic Pictures by Wireless. However, none of these bold predictions were ever realized.


One person attending the Saint Louis conference, Lee DeForest, was particularly impressed by Poulsen's invention, and would spend many years trying to develop arc-transmitters for audio transmissions, both for point-to-point communication and for broadcasting entertainment and news. Forced out of United Wireless in late 1906, DeForest formed the Radio Telephone Company, to promote "sparkless" arc-based transmission systems. But although DeForest made a number of well publicized experimental and publicity transmissions, he was ultimately unsuccessful in developing a reliable arc system. (A major problem likely was the fact that he never got around to purchasing the rights to use Poulsen's patents, which seems to have led to some hit-or-miss engineering work. In his autobiography, DeForest claimed, not very convincingly, that he had read that another inventor had anticipated Poulsen's development of the hydrogen arc, which meant it was all right for him to use it). According to his autobiography, on December 31, 1906 DeForest was able for the first time to transmit his voice across a room. He then moved rapidly, and prematurely, to develop commercial sales. Wireless 'Phone Transmits Music, from the March 7, 1907 New York Herald, reviewed test transmissions made in New York City of music produced by Thaddeus Cahill's electronic synthesizer, the Telharmonium. Reporting Yacht Races by Wireless Telephony from the August 10, 1907 Electrical World boasted that "The first actual application of radio-telephony to practical work anywhere in the world was made at Put-in-Bay, in Lake Erie, during the week of July 15 to 20, in reporting the regatta of the Interlake Association." Around October, 1907 -- details about the broadcast are poorly documented -- Eugenia Fararr sang two songs into DeForest's experimental transmitter located atop the Parker Building, which is thought to be the first live radio performance.

DeForest next promoted his system to the U.S. Navy, and in the October 12, 1907 issue of The Outlook, Wireless Telephones at Sea reported initial tests being conducted on the Connecticut and Virginia using his equipment, which included broadcasts of phonograph records from the Connecticut for the amusement of the other vessels. These tests were impressive enough for the Navy to have DeForest supply its "Great White Fleet" with 26 arc radiotelephones for an around-the-world voyage, and this innovation merited articles in two 1908 issues of Telephony magazine: Wireless Telephony in the Navy, by N. J. Quirk, appearing in January, and Wireless Telephony for the Navy, by Herbert T. Wade, which ran in May. Some experienced radio operators were unaware that radiotelephone experimentation had started, which could lead to humorous results, as a banner headline on the front page of the November 25, 1908 Hawaiian Star, Mysterious Voices Startled Him, reported that when the fleet visited Hawaii, one local operator "thought I heard the angels talking", although when the facts were sorted out, it led to speculation that the islands could set up a commercial service. Franklin Matthews' 1908 book, "With the Battle Fleet", included his first-hand impressions of the Fleet's Wireless Telephones, noting that although the innovation was "largely in the experimental and almost the infantile stage", naval electricians "were confident that as soon as certain difficulties were overcome, difficulties no more serious, they said, than the ordinary telephone encountered in the beginning, the apparatus would be workable as readily as a telephone on land." However, at this early stage the transmitters proved impracticable, and the Poulsen interests threatened a patent infringement lawsuit against the navy, so they were scraped at the end of the voyage, documented by reports such as Wireless Phone Hopeless Failure from the January 19, 1908 San Francisco Call, and Wireless Telephone On Battle Fleet a Total Failure from the August, 1909 Popular Mechanics. In The Radiotelephone Failure section of Linwood S. Howeth's 1963 History of Communications-Electronics in the United States Navy, the author wrote: "One of the first mistakes of the [USN Radio Division head Lt. Comdr. Cleland] Davis regime was that of becoming too quickly convinced of the capabilities and promises of the radiotelephone equipment by De Forest in the summer of 1907. Under ordinary circumstances De Forest equipment was noted for its lack of engineering design and perfection and under such hurried procurement the equipment delivered was far below this normal low quality."

DeForest was one of the first persons to suggest using radio signals to broadcast entertainment to a wide audience, and in the June, 1907 issue of The American Monthly Review of Reviews, Herbert T. Wade's Wireless Telephony by the De Forest System noted the possibilities for "the distribution of music from a central station", and also reported that "the inventor believes that by using four different forms of wave as many classes of music can be sent out as desired by the different subscribers". However, DeForest was also known for being excessively optimistic, as this review also reported, very prematurely, that "Dr. De Forest has reached the conclusion that wireless telephony on a practical and commercial scale has been realized." Wireless Telephony at Last from the June 15, 1907 The Literary Digest further reviewed radio-telephone systems developed by DeForest, and by Adolphus Slaby in Germany. Barnard Girls Test Wireless 'Phones, from the February 26, 1909 New York Times, reported on a test where Mrs. Stanton Blatch, DeForest's mother-in-law, used the new technology to promote the then-controversial idea that women should be allowed to vote. DeForest's later entertainment broadcasting efforts included an opera, direct from the Metropolitan Opera House in New York City, reviewed in Grand Opera by Wireless, in the March 5, 1910 issue of Telephony, plus a concert by Mme. Mariette Mazarin, reported by Radio Telephone Experiments in the May, 1910 issue of Modern Electrics. However, the Mazarin concert was the final effort for many years for his broadcasting experiments -- the technology for quality audio transmissions just did not exist yet. These technical issues, plus legal troubles, caused DeForest to suspend his development of arc-transmitters for audio transmissions, and it wouldn't be until 1916, following the introduction of vacuum-tube transmitters, that he would return to audio radio development.

A subsidiary, the Great Lakes Radio Telephone Company was formed, and the February 13, 1909 Coos Bay Times reported What The Wireless Telephone is Doing for the Great Lakes, as the company claimed it would soon provide radiotelephone communication between ships and the shore, in addition to the "supplying of music and other forms of entertainment to passengers traveling on the passenger vessels". The next day, De Forest Tells of a New Wireless in the New York Times included DeForest's completely incorrect prognostication that: "I confidently predict that within the next five years every ship of a certain size that goes to sea will be equipped with the wireless telephone". In the March 1, 1910 New-York Tribune, Wireless Sent Afar reported a successful exchange of radiotelegraph messages between stations in New York City and Milwaukee, Wisconsin, with DeForest quoted as saying "Commercial wireless service will be assured in 1910." This was reminiscent of the 1906 American DeForest proclamation of "transatlantic wireless now assured" and equally as inaccurate. The attempt to set up a point-to-point radiotelephone service along the Great Lakes also collapsed at this time, as reported in a short note appearing in the August 6, 1910 issue of Telephony: Great Lakes Wireless Telephone Out of Business. DeForest's various companies fell into bankruptcy, and he would soon face criminal charges for stock fraud. In 1911, DeForest was able to temporarily find employment at the one company that actually was operating a successful arc-transmitter radiotelegraph service, the Federal Telegraph Company.


Francis J. McCarty's short life did have one lasting impact -- he was indirectly responsible for the formation of one of the more successful, albeit least known, early U.S. radio companies. After graduating from Stanford University, Australian-born Cyril F. Elwell was hired by local businessmen to evaluate the commercial potential of the McCarty patents. This initially caused some conflict with the university, covered on the front page of the July 9, 1908 San Francisco Call: Phone Magnate Bars Wireless From Stanford. A few months later, the September 13, 1908 Call reported about a Test Given McCarty Wireless Telephone, which bridged a distance of one mile (1.5 kilometer). Elwell eventually concluded that the McCarty system was not practical, however, while doing this research he also determined that the Poulsen patents were commercially viable, and in 1909 helped organize a local syndicate to purchase the U.S. patent rights to Poulsen's arc-transmitter, with Elwell -- who by now had gained a reputation as A Wireless Expert, according to the March 3, 1910 Woodland Daily Democrat -- becoming President of a company set up in San Francisco. Shortly after the new company was founded, Elwell reviewed The Poulsen System of Wireless Telephony and Telegraphy in the April 2, 1910 issue of the Journal of Electricity, Power and Gas. (Although the arc-transmitter worked well, the automated high-speed telegraphing equipment reviewed in the article still needed some work, according to Charles V. Logwood's High Speed Radio Telegraphy, from the June, 1916 issue of The Electrical Experimenter.) An early demonstration of the Poulsen system, operating between Stockton and San Francisco -- also one of the few occasions when it was used to make an audio transmission -- was reported in "Yankee Doodle" Sung by Wireless, in the July 6, 1910 San Francisco Call.

Elwell's company was undercapitalized, and a new, larger company was formed, with Beach Thompson as President and Elwell the Chief Engineer. Local Men in Wireless Company, from the front page of the December 21, 1910 Call, reported the incorporation of a holding company, the Poulsen Wireless Company, although the enterprise was better known by the name of its operating company, Federal Telegraph. In the December 30, 1910, Hawaiian Gazette, Wireless Wizard to Work Wonders interviewed president Beach, who outlined the new company's ambitious plans. Federal Telegraph went on to produce progressively more powerful and sophisticated arc-transmitters for radiotelegraph use, and Wireless Across the U.S. by E. A. Mayne, from the May, 1911 Modern Electrics, reported the successful introduction of an overland radiotelegraph service, crossing the desert and Rocky Mountains between San Francisco and El Paso, Texas. A Federal Telegraph advertisement in the May 7, 1912 San Francisco Call offered its radiotelegraph "wireless service for Pacific Coast business", while Some Recent Developments of the Poulsen System of Wireless Telegraphy, by "W. C. R." from the July, 1912 Electrician and Mechanic, contrasted Federal's recent advances with the less successful attempts to develop the Poulsen system in Europe and Canada. Longest News Air Line in World "Bridges" Honolulu and This City, in the July 29, 1912 San Francisco Call, heralded the company's addition of a Hawaiian link as the "most distinctive achievement in the history of wireless telegraphy". The September 8, 1912 issue of the same newspaper further reviewed the Wireless Wonders Worked in San Francisco, as Federal Telegraph continued to expand its activities. However, although initially the company planned to establish a nationwide radiotelegraph service in addition to trans-Pacific links, the idea of a national service was eventually abandoned, and the company concentrated on a limited overland service in the west, plus extensive naval contracts.

In 1913, Cyril Elwell left Federal Telegraph, and Leonard Fuller, who organized critical basic research needed for increasing the power of the transmitters, became the company's new Chief Engineer. But Elwell continued to work as an Poulsen arc-transmitter designer on both sides of the Atlantic, and an article which appeared in the September 6, 1919 Electrical Review, Developments of Poulsen Wireless System Shown, reviewed Elwell's radiotelegraph station engineering work for the period from 1909 through 1919.

During World War One, the Navy Department asked the U.S. Congress for funds to purchase the Federal Telegraph radio stations and patents. This request was denied, however, the Navy then found in its budget the money needed to make the purchase anyway, which, not coincidentally, also served to block Marconi's South American activities. Following the sale of its stations, Federal Telegraph continued to operate a telegraph service in the west, but now over leased telephone wires. Then, after the war, an unhappy Congress found out about the Navy Department's purchase, which it felt was done through subtrafuge, and instructed the Navy to return the stations to their original owners. Dr. Washington Dodge, who had taken over as Federal president in 1917 and arranged the 1918 sale of most of the company's assets to the Navy, was later found to have used an intermediary company to pocket a large share of the sales fee, and was forced out as president in early January, 1919. Six months later, facing legal challenges to his actions, he committed suicide. A committee organized by new president R. P. Schwerin worked to untangle the company's finances, as reviewed in detail by Poulsen Wireless Company Presents Plans for Winding Up Its Entangled Affairs in the February 21, 1920 San Francisco Chronicle. (The company's complicated history was summerized in the Federal Telegraph Co. section of the 1922 Moodys Manual of Railroads and Corporation Securities.)

In late 1917, Federal Telegraph became the junior partner with American Marconi in forming the Pan-American Wireless Telegraph and Telephone Company, to develop a network of long-distance radiotelegraph links throughout South America. A New Wireless Chain Between the Americas by John V. L. Hogan, from the November, 1918 Popular Science Monthly, reviewed the proposed system in detail. Following World War One, Federal Telegraph found itself back in the radiotelegraph business, and the company's reorganization and expansion plans were explained by Acting Chief Engineer Haraden Pratt in New Stations of the Federal Tel. Co., from the February, 1921 Pacific Radio News. Despite Federal's various plans over the years -- including stations in China -- it ultimately proved unable to expand beyond its Pacific coast roots. Ironically, after years of suggesting that the radiotelegraph was destined to make landline telegraphs and undersea cables obsolete, Huge Radio System Started by Postal, from the August 25, 1927 New York Evening Post, announced that Federal Telegraph was being purchased by Mackay, an organization with extensive telegraph and cable holdings, although the new owner had plans for the "building up of a world-wide radio communication system". But, less than a year later, the June 26, 1928 Niagara Falls Gazette reported, in Series of Mergers Creates Impressive Radio Competition, that Mackay had in turn been swallowed up, by the International Telegraph and Telephone Company.


In early 1909, Charles D. Herrold established the Herrold College of Engineering and Wireless in San Jose, California. As part of the school's activities he built a radio station located atop that city's Garden City Bank building, for experimental work with high-frequency spark and arc transmitters, initially using the callsigns of FNFN and SJN, and later receiving an experimental licence as 6XF. The station became known for making experimental entertainment broadcasts, in order to publicize the school and attract students. Herrold also appears to be the first person to broadcast entertainment programs on a regular schedule, beginning in 1912 -- an early report of his broadcasting activities appeared in the July 21, 1912 San Jose Mercury Herald, which announced that Herrold Will Give Concert By Wireless Telephone, while the next day's San Jose Evening News reported Wireless Telephone Proves Successful. In addition to his school, Herrold worked to develop a commercial radio-telephone system that could be marketed to clients such as the U.S. Navy. In March, 1912, the National Wireless Telephone and Telegraph Company, headquartered in San Francisco, was incorporated, and a few months later Herrold began doing developmental work with the firm, becoming its chief engineer. National Wireless built a group of stations in central California, of which the most prominent, which later received an experimental licence as 6XO, was located on the roof of the Fairmont Hotel in San Francisco. In the December 10, 1922 issue of the Mercury Herald, Emile Portal, who had been one of Herrold's students, and later worked with him professionally, reviewed the events which had occurred a decade earlier in Former San Jose Boy Now Foremost Expert in Radio, as Portal recalled the weekly broadcasts from the Garden City Bank station, plus his own work at the Fairmont Hotel station, "where more ambitious programs than those sent from his San Jose station were broadcasted". (In his memoirs, Robert H. Marriott reported that "...in July, 1915, I stopped at the Panama Pacific Exposition... In San Francisco I visited a station on the roof of the Fairmont Hotel, where phonograph records and local-talent music programs were being broadcast with an arc in alcohol vapor.")

The January 30, 1912 San Jose Mercury Herald reported successful radio-telephone tests between the Fairmont Hotel station and a U.S. navy station at Mare Island, with the hopes for even greater distances in the future expressed in the title of the review: "Hello Frisco, 1--9--1--5----This is Honolulu". In the July 27, 1913 issue of the same newspaper, San Jose Scientist Achieves Distinction reported Herrold's success in establishing a radio-telephone link between the stations at San Jose and San Francisco, as the inventor claimed to have developed "the most simple and practical system yet put in operation, in this country or abroad". A short review of his work by Milton E. Hymes, Correspondence, which appeared in the November, 1913 The Electrical Experimenter, reported that the transmission of the song "The Trail of the Lonesome Pine" had been heard 900 miles (1,450 kilometers) away, and in the April, 1914 issue of the same magazine, University of California Doing Good Radio Work reviewed additional radio-telegraph and radio-telephone activities. Despite on-going development, Herrold was never able to produce a commercial product, and in late 1913 had a falling-out with National Wireless and sued his former employer, only to have his successor, in Rival Engineer Testifies from the April 9, 1915 San Jose Mercury Herald, claim that "most of the improvements made by Herrold were ultimately abandoned by the company".

Herrold continued to operate the arc transmitter at his school, as documented by articles in the San Jose Mercury Herald, with Wireless Music Christmas Day on December 24, 1916 telling of an upcoming seasonal concert, while two days later Concert by Wireless Heard by 300 People reported that listeners had successfully received the 20 minute program "by connecting their own wireless apparatuses with the central apparatus of the Herrold-Portal aerial system of telephony", and a week later, Pistol Shot by Wireless as Old Year Goes publicized a New Year's Eve broadcast. In addition, the January 15, 1917 The Talking Machine World's Music Through the Air reported on a recent test transmission from the Fairmont Hotel station. However, these would be some of the last audio transmissions made by an arc-transmitter. In April, 1917, the stations were shut down due to the start of World War One, moreover, despite their relative refinement, arc transmitters had already become an obsolete technology for audio transmissions, due to the development of vacuum-tube transmitters.


In 1912, the U.S. Navy constructed a new station, NAA in Arlington, Virginia, as the first in a chain of high-power international links. This station initially used a 100 kilowatt NESCO rotary-spark transmitter designed by Reginald Fessenden. However, as recounted in The Federal Telegraph Co. of California and the Poulsen Arc Transmitter and The Radio (Arlington), Virginia, Station sections of Linwood S. Howeth's 1963 History of Communications-Electronics in the United States Navy, Cyril Elwell convinced the Navy to grudgingly let Federal Telegraph install a 35 kilowatt arc-transmitter for comparison trials. The Navy was amazed to find that the compact and virtually silent arc-transmitter outperformed the rotary-spark set, even though it was using just 1/3rd the power. At this point the Navy made an abrupt shift in its policies, and made increasingly powerful Federal Telegraph arcs the predominant transmitters in its new installations, as described in the Development of the High-Powered Chain chapter of Howeth's book. (Ironically, in a comprehensive paper on continuous-wave transmitters presented before the American Institute of Electrical Engineers in 1908, Fessenden had dismissed Poulsen's approach as an inefficient step backward from earlier researchers, worth mentioning in passing only "on account of the interest it appears to have excited in Europe").


Numerous companies on both sides of the Atlantic and in Japan tried developing arc-transmitters for audio transmissions, and over the years, Poulsen licenced the rights to his arc-transmitter patents to a variety of firms, while others seem to have developed arc-transmitters without first obtaining permission from the rights holders. A. Frederick Collins developed an arc-transmitter system which was reviewed in The Collins System of Long-Distance Wireless Telephony in the September 19, 1908 Scientific American, and in greater detail by William Dubilier's Wireless Telephony chapter in the 1909 book Wireless Telegraphy and High Frequency Electricity. The October 15, 1909 Flint Daily Journal reported on the efforts by M. F. Brown of Los Angeles in Music by Wireless Is Plan of Company Formed in Chicago, but there is no evidence that this effort got beyond the idea stage.

For eighteen months in 1908-1909, equipment designed by a German company, Telefunken, was evaluated by the U.S. Army Signal Corps in New York Harbor -- in Experiences in Wireless Telephoning, from the April, 1912 Electrician and Mechanic, Austin C. Lescarboura reported that "the practicability of the wireless telephone was found to be uncertain". However, a few months later Telefunken reported success, which made it possible to Hear Music by Wireless on a ship in the North Atlantic, transmitted from its Long Island, New York station, according to the March 1, 1913 The Music Trade Review. Boy Experts in Wireless Telephoning, from the October 8, 1911 New York Herald, reviewed the low-powered experiments being made by the Junior Wireless Club. In the October 27, 1912 Brooklyn Daily Eagle, Young Brooklynite Talks by Wireless reviewed the work of Elman B. Myers.

American Marconi also did some limited development of arc transmitters in the United States, with information on test transmissions from a station located atop the Wanamaker's department store reviewed in New York to Philadelphia by Wireless Telephone in the June 1914 issue of The Wireless Age and Wireless 'Phone Used from the May 31, 1914 Oregonian. The next year the company, somewhat belatedly, purchased the English rights to use the Poulsen patents, announced in Marconi Absorbs Rival from the September 15, 1915 New York Times, just as the technology was becoming obsolete for audio transmissions due to the development of vacuum-tube transmitters. Wireless System To Aid Commerce Of Pan-America, from the December 26, 1917 New-York Tribune, announced the creation of the Pan-American Wireless Telegraph and Telephone Company, a joint venture with Federal Telegraph, with Marconi acting as the senior partner. This new company intended to build arc radiotelegraph stations, after the conclusion of World War One, to "connect all of the Americas for commercial wireless communication". However, Edward J. Nally, general manager of American Marconi, and president of the new corporation, was guilty of wishful thinking when he claimed this was an "enterprise the United States government has set its seal of approval" -- actually the U.S. government was opposed to what it saw as undue British influence, and would help to block the new company's efforts.

C. D. Tuska developed his own form of arc transmitter, using tungsten electrodes, reviewed in Hartford Youths Construct an Efficient Wireless Telephone from the March 19, 1916 Hartford Courant, which he used to broadcast occasional concerts.

Overall, although arc-transmitters were a significant advance over spark transmitters, they still were somewhat complicated, generally limited to radiotelegraphy, and were relatively quickly supplanted by the development of vacuum-tube transmitters, which were even more efficient and reliable. (In his 1922 book Amateur Radio, Maurice J. Grainger, writing about the superiority of vacuum-tube transmitters for broadcasting purposes, wrote "Certainly an arc transmitter could be used, but the sounds that would be projected through the air by this means would be so inextricably mixed up with 'clicks, hisses, gurgles and howls' that nobody would have the patience to listen to it.")

"In 1903, Poulsen raised the arc to the status of a practically operative generator of radio frequency energy in considerable quantity by the following changes: placing the entire arc in an atmosphere of hydrogen or a hydrocarbon vapor (e.g., alcohol or gasoline), using a carbon electrode for the negative side and a copper anode water-cooled for the positive side, rotating the carbon electrode slowly by motor drive, and placing an intense deflecting magnetic field transverse to the arc. Except for certain constructional and electrical details, this is the Poulsen arc of to-day."--Alfred N. Goldsmith, Radio Telephony, 1918.