Ralph Vinton Lyon Hartley (November 30, 1888 – May 1, 1970) was an American

electronics Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other Electric charge, electrically charged particles. It is a subfield ...

researcher. He invented the Hartley oscillator and the Hartley transform, and contributed to the foundations of

information theory Information theory is the mathematical study of the quantification (science), quantification, Data storage, storage, and telecommunications, communication of information. The field was established and formalized by Claude Shannon in the 1940s, ...

. His legacy includes the naming of the hartley, a unit of information equal to one decimal digit, after him.

Biography

Hartley was born in Sprucemont, Nevada, and attended the

University of Utah The University of Utah (the U, U of U, or simply Utah) is a public university, public research university in Salt Lake City, Utah, United States. It was established in 1850 as the University of Deseret (Book of Mormon), Deseret by the General A ...

, receiving an A.B. degree in 1909. He became a

Rhodes Scholar The Rhodes Scholarship is an international Postgraduate education, postgraduate award for students to study at the University of Oxford in Oxford, United Kingdom. The scholarship is open to people from all backgrounds around the world. Esta ...

at St Johns,

Oxford University The University of Oxford is a collegiate research university in Oxford, England. There is evidence of teaching as early as 1096, making it the oldest university in the English-speaking world and the second-oldest continuously operating u ...

, in 1910 and received a B.A. degree in 1912 and a B.Sc. degree in 1913. He married Florence Vail of

Brooklyn Brooklyn is a Boroughs of New York City, borough of New York City located at the westernmost end of Long Island in the New York (state), State of New York. Formerly an independent city, the borough is coextensive with Kings County, one of twelv ...

on March 21, 1916. The Hartleys had no children. He returned to the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

and was employed at the Research Laboratory of the Western Electric Company. In 1915 he was in charge of

radio receiver In radio communications, a radio receiver, also known as a receiver, a wireless, or simply a radio, is an electronic device that receives radio waves and converts the information carried by them to a usable form. It is used with an antenna. ...

development for the Bell System transatlantic

radiotelephone A radiotelephone (or radiophone), abbreviated RT, is a radio communication system for conducting a conversation; radiotelephony means telephony by radio. It is in contrast to ''radiotelegraphy'', which is radio transmission of telegrams (messag ...

tests. For this he developed the Hartley oscillator and also a neutralizing circuit to eliminate triode singing resulting from internal coupling. A

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an sufficiency of disclosure, enabling discl ...

for the oscillator was filed on June 1, 1915 and awarded on October 26, 1920. During

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

Hartley established the principles that led to sound-type directional finders. Following the war he returned to Western Electric. He later worked at Bell Laboratories. He performed research on repeaters and voice and carrier transmission and formulated the law "that the total amount of information that can be transmitted is proportional to frequency range transmitted and the time of the transmission." His 1928 paper is considered "the single most important prerequisite" for Shannon's theory of information. After about 10 years of illness he returned to Bell Labs in 1939 as a

consultant A consultant (from "to deliberate") is a professional (also known as ''expert'', ''specialist'', see variations of meaning below) who provides advice or services in an area of specialization (generally to medium or large-size corporations). Cons ...

. In spite of his illness during most of the 1930s, Hartley had formed a theoretical and experimental research group at Bell Laboratories starting in 1929 to investigate nonlinear oscillations and what later became known as parametric amplifiers. This research was mostly parallel to the work being done at the same time in Soviet Russia by Leonid Mandelstam and in Europe by Balthasar van der Pol. A short review and extensive bibliography was published by Mumford in 1960. The Bell Laboratories work was carried on under Hartley's guidance during the 1930s and 1940s by John Burton and Eugene Peterson (who themselves had begun investigations of nonlinear circuits as far back as 1917 when they had observed unusual characteristics while working with E.F.W. Alexanderson's magnetic modulators, an early form of magnetic amplifier). Peterson later got John Manley and Harrison Rowe involved in this line of research during the 1940s which culminated in the now famous Manley–Rowe relations and several papers by the latter two authorsManley J.M., Rowe H.E., "General Energy Relations in Nonlinear Reactances", ''

Proceedings of the IRE The ''Proceedings of the IEEE'' is a monthly peer-reviewed scientific journal published by the Institute of Electrical and Electronics Engineers (IEEE). The journal focuses on electrical engineering and computer science. According to the ''Journa ...

'', Volume 47, December 1959, pp 2115–2116 on the topic of parametric circuits in the mid 1950s. During

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

he was particularly involved with

servomechanism In mechanical and control engineering, a servomechanism (also called servo system, or simply servo) is a control system for the position and its time derivatives, such as velocity, of a mechanical system. It often includes a servomotor, and ...

problems. He retired from Bell Labs in 1950 and died on May 1, 1970.

Awards

IRE Medal of Honor The IEEE Medal of Honor is the highest recognition of the American Institute of Electrical and Electronics Engineers (IEEE). It has been awarded since 1917, and is presented to an individual or team of up to three who have made exceptional contri ...

, 1946, for his oscillator and information proportionality law. This was an award from the

Institute of Radio Engineers The Institute of Radio Engineers (IRE) was a professional organization which existed from 1912 until December 31, 1962. On January 1, 1963, it merged with the American Institute of Electrical Engineers (AIEE) to form the Institute of Electrical ...

which later merged into the

Institute of Electrical and Electronics Engineers The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines. The IEEE has a corporate office ...

; the award became the IEEE Medal of Honor. * Fellow of the

American Association for the Advancement of Science The American Association for the Advancement of Science (AAAS) is a United States–based international nonprofit with the stated mission of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsib ...

Publications

''Probably incomplete.'' * Hartley, R.V.L.,
The Function of Phase Difference in the Binaural Location of Pure Tones
" '' Physical Review'', Volume 13, Issue 6, pp 373–385, (June 1919). * Hartley, R.V.L., Fry T.C.,"The Binaural Location of Pure Tones", '' Physical Review'', Volume 18, Issue 6, pp 431 – 442, (December 1921). * Hartley, R.V.L., "Relations of Carrier and Side-Bands in Radio Transmission", ''

'', Volume 11, Issue 1, pp 34 – 56, (February 1923). * Hartley, R.V.L.
"Transmission of Information"
'' Bell System Technical Journal'', Volume 7, Number 3, pp. 535–563, (July 1928). * Hartley, R.V.L., "A Wave Mechanism of Quantum Phenomena", '' Physical Review'', Volume 33, Issue 2, Page 289, (1929) (abstract only) * Hartley, R.V.L., "Oscillations in Systems with Non-Linear Reactance", '' The Bell System Technical Journal'', Volume 15, Number 3, pp 424 – 440, (July 1936). *Hartley, R.V.L., "Excitation of Raman Spectra with the Aid of Optical Catalysers", ''

Nature Nature is an inherent character or constitution, particularly of the Ecosphere (planetary), ecosphere or the universe as a whole. In this general sense nature refers to the Scientific law, laws, elements and phenomenon, phenomena of the physic ...

'', Volume 139, pg 329 - 329, (20 February 1937) * Hartley, R.V.L., "Steady State Delay as Related to Aperiodic Signals", '' Bell System Technical Journal'', Volume 20, Number 2, pp 222 – 234, (April 1941). * Hartley, R.V.L., "A More Symmetrical Fourier Analysis Applied to Transmission Problems," ''

'', Volume 30, Number 2, pp. 144–150 (March 1942). * Hartley, R.V.L., "Note on the Application of Vector Analysis to the Wave Equation", '' Journal of the Acoustical Society of America'', Volume 22, Issue 4, pg 511, (1950). * Hartley, R.V.L., "The Significance of Nonclassical Statistics", ''

Science Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which stu ...

'', Volume 111, Number 2891, pp 574 – 576, (May 26, 1950) * Hartley, R.V.L., "Matter, a Mode of Motion", '' Bell System Technical Journal'', Volume 29, Number 3, pg 350 - 368, (July 1950). * Hartley, R.V.L., "The Reflection of Diverging Waves by a Gyrostatic Medium", '' Bell System Technical Journal'', Volume 29, Number 3, pp 369 – 389, (July 1950), * Hartley, R.V.L., "A New System of Logarithmic Units", ''

'', Volume. 43, Number 1, pg 97, (January 1955). * Hartley, R.V.L., "New System of Logarithmic Units", '' Journal of the Acoustical Society of America'', Volume 27, Issue 1, pp 174 – 176, (1955) * Hartley, R.V.L., "Information Theory of The Fourier Analysis and Wave Mechanics", August 10, 1955, publication information unknown. * Hartley, R.V.L., "The Mass of a Wave Particle", July 30, 1955, unpublished manuscript, copies available from the Niels Bohr Library & Archives, American Institute of Physics, College Park MD * Hartley, R.V.L., "The Mechanism of Gravitation", January 11, 1956, unpublished manuscript; copies available from the Niels Bohr Library & Archives, American Institute of Physics, College Park MD * Hartley, R.V.L., "The Mechanism of Electricity and Magnetism", June 14, 1956, unpublished manuscript, copies available from the Niels Bohr Library & Archives, American Institute of Physics, College Park MD * Hartley, R.V.L., "Rotational Waves in a Turbulent Liquid", '' Journal of the Acoustical Society of America'', Volume 29, Issue 2, pp 195 – 196, (1957) * Hartley, R.V.L., "A Mechanistic Theory of Extra-Atomic Physics",''

Philosophy of Science Philosophy of science is the branch of philosophy concerned with the foundations, methods, and implications of science. Amongst its central questions are the difference between science and non-science, the reliability of scientific theories, ...

'', Volume 26, Number 4, pp 295 – 309, (October 1959)

Notes

References

Ralph V. L. Hartley, Legacies, IEEE History Center
updated July 7, 2011 * US Patent 1,356,763, Oscillation Generator, October 26, 1920, United States Patent and Trademark Office

page images can be downloaded. * US Patent 1,666,206, Modulation System, April 17, 1928, United States Patent and Trademark Office

page images can be downloaded.

External links

Archival collections

Ralph V. L. Hartley papers, 1920-1970, Niels Bohr Library & Archives
{{DEFAULTSORT:Hartley, Ralph 1888 births 1970 deaths Alumni of St John's College, Oxford American Rhodes Scholars American electronics engineers Fellows of the American Association for the Advancement of Science IEEE Medal of Honor recipients American information theorists Scientists at Bell Labs University of Utah alumni 20th-century American inventors Fellows of the American Physical Society Inventors from Nevada