Harry Shoemaker
Harry Shoemaker was an American inventor and pioneer radio engineer, who received more than 40 U.S. patents in the radio field from 1901 to 1905. His transmitter and receiver designs set the standard for the U. S. commercial radio industry up to World War One.
Early life
Shoemaker was born in 1879 near Millville, Pennsylvania. His early education was at the Greenwood Seminary in Millville, Pennsylvania and the Normal School in Muncy, Pennsylvania. In 1896, he began attending Pennsylvania State College.In 1894, Professor Henry Russell conducted a classroom demonstration of the transmission and reception of electromagnetic radiation. A fascinated Shoemaker conducted further experiments at his home, using a spark-gap transmitter, plus a coherer receiver of his own design, which used a galvanometer's needle to strike and reset the coherer after each received Morse code signal. However, he did not publicize or patent any of his early work, so when he later testified that he had constructed a radiotelegraph system, in April 1895 at the age of 16, which anticipated Guglielmo Marconi's original patent, the U.S. courts would not accept his statement, bluntly declaring that "His testimony is so utterly unsupported and insufficient and improbable that it will not be discussed".
Career history
Gehring companies
In November 1899, Dr. Gustave P. Gehring of Philadelphia, a gold mine and real estate promoter, established the American Wireless Telephone and Telegraph Company, which was the first radio communications firm established in the United States. This corporation initially claimed to have a monopoly on all wireless communication in the United States, based on U.S. patent number 350,299, a short-range wireless communication system using magnetic induction that had been issued in 1886 to Amos Dolbear.American Wireless and its subsidiaries primarily engaged in the florid promotion of stock sales at inflated prices to the unwary, and did only limited legitimate work toward its supposed goal of setting up a nationwide radiotelegraphic system. However, it also employed a small number of capable engineers. At its founding A. Frederick Collins was the lead technical employee, but he soon left the firm and was replaced by Shoemaker as American Wireless' Chief Engineer. In 1901 the company built stations in New Jersey to report the Columbia vs. the Shamrock international yacht races by radio, although interference from two other companies limited the transmission's effectiveness.
Shoemaker proved to be a prolific worker, and received numerous patents for improvements in radio sending and receiving equipment. Most early spark transmitters were powered by batteries or Leyden jars. Shoemaker developed an improved design, which used 120-cycle alternating current, which provided more power for stronger signals, and also produced a distinctive sound that made it easier for a transmission to be heard on congested wavelengths.
In 1902, Gehring merged American Wireless with most of its subsidiaries to form the Consolidated Wireless Telephone and Telegraph Company, and the next year a further reorganization resulted in the International Wireless Telegraph and Telephone Company. Shoemaker continued as Chief Engineer throughout these restructurings. In early 1904, International Wireless was taken over by the American DeForest Wireless Telegraph Company, which thereby acquired Shoemaker's services and the use of his valuable patents. He received a Silver Medal as Collaborator for his work at the company's exhibit at the 1904 Louisiana Purchase Exposition in Saint Louis, Missouri, and was put in charge of American DeForest's factory in Jersey City, New Jersey.
International Telegraph Construction Company
Shoemaker soon left American DeForest, joining with Col. John Firth to form his own company, the International Telegraph Construction Company, in Jersey City, New Jersey. In 1905, he constructed a set of radio-controlled naval torpedoes, which, after unsuccessfully trying to interest the U.S. government, were sold to the Japanese navy. By the end of 1906, the U.S. Navy had purchased three land and eighteen shipboard transmitters from the firm, and the company's equipment was "regarded as the best of its time by naval radio operators". Shoemaker's company also produced high voltage transmitting and variable receiver condensers, and wave meters and other measuring instruments.United Wireless Telegraph Company
In late 1906, the American DeForest company was reorganized as the United Wireless Telegraph Company, but it continued to use some equipment originally designed by Shoemaker. In July 1908 United Wireless president Christopher Columbus Wilson engineered Shoemaker's return by the expedient of buying a controlling interest in International Telegraph company stock, and the firm was then merged with United Wireless operations, which was the largest in the United States at this time. Shoemaker become Chief Engineer of United Wireless, and his factory began to produce equipment designed for its installations.In 1909 he was elected as one of the vice presidents of the newly formed The Wireless Institute of New York City, and in 1912 became a founding member of Institute of Radio Engineers.