Radio Broadcast (May-Oct 1922)

230 Radio Broadcast action photographs of famous golfers, and near by stands a bag of golf clubs as though in readiness for a trip to the Country Club. Several guns which he delights to clean as well as shoot are a source of especial pride to him. In addition to out-of-door pursuits, he snatches moments of relaxation now and then, and often an upturned book shows that he has been interrupted in reading " Curiosities of Literature" by Disraeli, or other of his favorite authors. Although born in Bolton, Canada, in the year 1866, and a volunteer with the First Canadian Contingent, and detailed to the War Office, London, by General Sam Hughes in 1914, he is proud to call himself a Yankee, and explains with pride that the first of his name to live in this country was John Fessenden, an original settler of Cambridge, Mass., whose tan yard was somewhere on the site of the present Harvard College Yard. At the age of nineteen he was appointed inspecting engineer of the General Electric Company, and later was head chemist for Edison, to whose instructions he attributes whatever success he has had in inventing. He has been professor of physics and electrical engineering at Purdue University, later at Pittsburgh, special agent for the United States Weather Bureau, and consulting engineer for the Submarine Signal Company. Of recent years, however, he has felt it impossible to continue his more public work, and is devoting himself entirely to his inventions and experiments, all of which he realizes are of great practical value and of immense service to the world. His seemingly superhuman accomplishments have been the result of a life-time of continuous and painstaking effort. As a child he was interested in mathematics. The banking profession, in which he was brought up, offered no incentive to his already inventive type of mind, and science, with its unceasing appeals to the imagination, excited him. In 1892 he was giving a course in Hertzian waves at Purdue University, and from that time to the present has added one marvellous device after another to the development of wireless communication. In endeavoring to transmit speech by wireless, he found it impossible with the old spark gap coherer system, because of the lack of two essential requirements, that the waves should be generated continuously and that the receiver should be capable of utilizing them continuously. In 1899 he started four lines of work for producing continuous waves, first by commutating a continuous current, second by a continuous arc, third by a high frequency dynamo, and fourth by an unstable current. He succeeded in 1900 in first transmitting articulate speech by wireless over a distance of one mile at Cobb Point, Maryland, using a 10,000 cycle per second commutator. Though understandable, the articulation was not perfectly clear. With the development of the continuous arc generation method, he was able in 1902 to reach approximately 12 miles by using an arc frequency of 50,000 cycles per second, producing much clearer articulation. In 1903 in Washington he demonstrated before a number of prominent engineers an apparatus capable of working 25 miles, which was put on the market and and tendered to the United States Navy in 1905. In the mean time he had proceeded with the development of the high frequency alternator and finally constructed three dynamos at the Brant Rock, Mass., station, two of them operating at 50,000 cycles, by using the fields of a previous dynamo failure, and a third operating at 100,000 cycles. For a continuous receiver, in place of the old coherer which had to be tapped back every time a signal was received, he invented a number of devices, the first of which was the ring receiver mounted on a sensitive microphonic contact, followed by the hot-wire barretter and the liquid barretter. About this time he devised an interesting type of receiver in which a small hot-wire barretter m^ounted on a small rubber holder fitted inside the ear, invisible wires ran to the hat-band and down the side of the body, permitting wireless telephone messages to be received by a person walking about in the fields several rniles from a station. After building various types of amplifiers, he was able to maintain regular wireless telephone communication between Brant Rock and Jamaica, L. 1., with articulation clearer than over the wire telephone lines between the same places, using an apparatus in 1907 which permitted simultaneous talking and listening. In 1906 he had been able to demonstrate to a number of leading scientists the transmission of speech by wireless between Plymouth and Brant Rock, and the relaying of conversation over the regular wire lines. As the result of tests made by the Bell Telephone Company, contracts were drawn up by