Ralph Hartley
Encyclopedia
Ralph Vinton Lyon Hartley (November 30, 1888 – May 1, 1970) was an electronics
researcher. He invented the Hartley oscillator
and the Hartley transform
, and contributed to the foundations of information theory
.
, receiving an A.B. degree in 1909. He became a Rhodes Scholar
at St Johns
, Oxford University
, in 1910 and received a B.A. degree in 1912 and a B.Sc. degree in 1913. He married Florence Vail of Brooklyn
on March 21, 1916. The Hartleys had no children.
He returned to the United States
and was employed at the Research Laboratory of the Western Electric Company
. In 1915 he was in charge of radio receiver development for the Bell System
transatlantic radiotelephone
tests. For this he developed the Hartley oscillator and also a neutralizing circuit to eliminate triode singing resulting from internal coupling. A patent
for the oscillator was filed on June 1, 1915 and awarded on October 26, 1920.
During World War I
he 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 repeater
s 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." After about 10 years of illness he returned to Bell Labs in 1939 as a consultant
.
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 authors on the topic of parametric circuits in the mid 1950's.
During World War II
he was particularly involved with servomechanism
problems.
He retired from Bell Labs in 1950 and died on May 1, 1970.
Electronics
Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...
researcher. He invented the Hartley oscillator
Hartley oscillator
The Hartley oscillator is an electronic oscillator circuit that uses an inductor and a capacitor in parallel to determine the frequency. Invented in 1915 by American engineer Ralph Hartley, the distinguishing feature of the Hartley circuit is that the feedback needed for oscillation is taken from...
and the Hartley transform
Hartley transform
In mathematics, the Hartley transform is an integral transform closely related to the Fourier transform, but which transforms real-valued functions to real-valued functions. It was proposed as an alternative to the Fourier transform by R. V. L. Hartley in 1942, and is one of many known...
, and contributed to the foundations of information theory
Information theory
Information theory is a branch of applied mathematics and electrical engineering involving the quantification of information. Information theory was developed by Claude E. Shannon to find fundamental limits on signal processing operations such as compressing data and on reliably storing and...
.
Biography
Hartley was born in Spruce, Nevada, USA and attended the University of UtahUniversity of Utah
The University of Utah, also known as the U or the U of U, is a public, coeducational research university in Salt Lake City, Utah, United States. The university was established in 1850 as the University of Deseret by the General Assembly of the provisional State of Deseret, making it Utah's oldest...
, receiving an A.B. degree in 1909. He became a Rhodes Scholar
Rhodes Scholarship
The Rhodes Scholarship, named after Cecil Rhodes, is an international postgraduate award for study at the University of Oxford. It was the first large-scale programme of international scholarships, and is widely considered the "world's most prestigious scholarship" by many public sources such as...
at St Johns
St John's College, Oxford
__FORCETOC__St John's College is a constituent college of the University of Oxford, one of the larger Oxford colleges with approximately 390 undergraduates, 200 postgraduates and over 100 academic staff. It was founded by Sir Thomas White, a merchant, in 1555, whose heart is buried in the chapel of...
, Oxford University
University of Oxford
The University of Oxford is a university located in Oxford, United Kingdom. It is the second-oldest surviving university in the world and the oldest in the English-speaking world. Although its exact date of foundation is unclear, there is evidence of teaching as far back as 1096...
, in 1910 and received a B.A. degree in 1912 and a B.Sc. degree in 1913. He married Florence Vail of Brooklyn
Brooklyn
Brooklyn is the most populous of New York City's five boroughs, with nearly 2.6 million residents, and the second-largest in area. Since 1896, Brooklyn has had the same boundaries as Kings County, which is now the most populous county in New York State and the second-most densely populated...
on March 21, 1916. The Hartleys had no children.
He returned to the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and was employed at the Research Laboratory of the Western Electric Company
Western Electric
Western Electric Company was an American electrical engineering company, the manufacturing arm of AT&T from 1881 to 1995. It was the scene of a number of technological innovations and also some seminal developments in industrial management...
. In 1915 he was in charge of radio receiver development for the Bell System
Bell System
The Bell System was the American Bell Telephone Company and then, subsequently, AT&T led system which provided telephone services to much of the United States and Canada from 1877 to 1984, at various times as a monopoly. In 1984, the company was broken up into separate companies, by a U.S...
transatlantic radiotelephone
Radiotelephone
A radiotelephone is a communications system for transmission of speech over radio. Radiotelephone systems are not necessarily interconnected with the public "land line" telephone network. "Radiotelephone" is often used to describe the usage of radio spectrum where it is important to distinguish the...
tests. For this he developed the Hartley oscillator and also a neutralizing circuit to eliminate triode singing resulting from internal coupling. A patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
for the oscillator was filed on June 1, 1915 and awarded on October 26, 1920.
During World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
he established the principles that led to sound-type directional finders
Radio direction finder
A radio direction finder is a device for finding the direction to a radio source. Due to low frequency propagation characteristic to travel very long distances and "over the horizon", it makes a particularly good navigation system for ships, small boats, and aircraft that might be some distance...
.
Following the war he returned to Western Electric
Western Electric
Western Electric Company was an American electrical engineering company, the manufacturing arm of AT&T from 1881 to 1995. It was the scene of a number of technological innovations and also some seminal developments in industrial management...
. He later worked at Bell Laboratories. He performed research on repeater
Repeater
A repeater is an electronic device that receives asignal and retransmits it at a higher level and/or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances.-Description:...
s 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." After about 10 years of illness he returned to Bell Labs in 1939 as a consultant
Consultant
A consultant is a professional who provides professional or expert advice in a particular area such as management, accountancy, the environment, entertainment, technology, law , human resources, marketing, emergency management, food production, medicine, finance, life management, economics, public...
.
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
Ernst Alexanderson
Ernst Frederick Werner Alexanderson was a Swedish-American electrical engineer, who was a pioneer in radio and television development.-Background:...
's magnetic modulators, an early form of magnetic amplifier
Magnetic amplifier
The magnetic amplifier is an electromagnetic device for amplifying electrical signals. The magnetic amplifier was invented early in the 20th century, and was used as an alternative to vacuum tube amplifiers where robustness and high current capacity were required...
). 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 authors on the topic of parametric circuits in the mid 1950's.
During World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
he was particularly involved with servomechanism
Servomechanism
thumb|right|200px|Industrial servomotorThe grey/green cylinder is the [[Brush |brush-type]] [[DC motor]]. The black section at the bottom contains the [[Epicyclic gearing|planetary]] [[Reduction drive|reduction gear]], and the black object on top of the motor is the optical [[rotary encoder]] for...
problems.
He retired from Bell Labs in 1950 and died on May 1, 1970.
Awards
- IRE Medal of HonorIEEE Medal of HonorThe IEEE Medal of Honor is the highest recognition of the Institute of Electrical and Electronics Engineers . It has been awarded since 1917, when its first recipient was Major Edwin H. Armstrong. It is given for an exceptional contribution or an extraordinary career in the IEEE fields of...
, 1946, for his oscillator and information proportionality law. This was an award from the Institute of Radio EngineersInstitute of Radio EngineersThe Institute of Radio Engineers was a professional organization which existed from 1912 until January 1, 1963, when it merged with the American Institute of Electrical Engineers to form the Institute of Electrical and Electronics Engineers .-Founding:Following several attempts to form a...
which later merged into the Institute of Electrical and Electronics EngineersInstitute of Electrical and Electronics EngineersThe Institute of Electrical and Electronics Engineers is a non-profit professional association headquartered in New York City that is dedicated to advancing technological innovation and excellence...
; the award became the IEEE Medal of HonorIEEE Medal of HonorThe IEEE Medal of Honor is the highest recognition of the Institute of Electrical and Electronics Engineers . It has been awarded since 1917, when its first recipient was Major Edwin H. Armstrong. It is given for an exceptional contribution or an extraordinary career in the IEEE fields of...
. - Fellow of the American Association for the Advancement of ScienceAmerican Association for the Advancement of ScienceThe American Association for the Advancement of Science is an international non-profit organization with the stated goals of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsibility, and supporting scientific education and science outreach for the...
Publications
Probably incomplete.- Hartley, R.V.L., "The Function of Phase Difference in the Binaural Location of Pure Tones," Physical ReviewPhysical ReviewPhysical Review is an American scientific journal founded in 1893 by Edward Nichols. It publishes original research and scientific and literature reviews on all aspects of physics. It is published by the American Physical Society. The journal is in its third series, and is split in several...
, Volume 13, Issue 6, pp 373–385, (June 1919). - Hartley, R.V.L., Fry T.C.,"The Binaural Location of Pure Tones", Physical ReviewPhysical ReviewPhysical Review is an American scientific journal founded in 1893 by Edward Nichols. It publishes original research and scientific and literature reviews on all aspects of physics. It is published by the American Physical Society. The journal is in its third series, and is split in several...
, Volume 18, Issue 6, pp 431 – 442, (December 1921). - Hartley, R.V.L., "Relations of Carrier and Side-Bands in Radio Transmission", Proceedings of the IRE, Volume 11, Issue 1, pp 34 – 56, (February 1923).
- Hartley, R.V.L., "Transmission of Information", Bell System Technical JournalBell System Technical JournalThe Bell System Technical Journal was the in-house scientific journal of Bell Labs that was published from 1922 to 1983.- Notable papers :...
, Volume 7, Number 3, pp. 535–563, (July 1928). - Hartley, R.V.L., "A Wave Mechanism of Quantum Phenomena", Physical ReviewPhysical ReviewPhysical Review is an American scientific journal founded in 1893 by Edward Nichols. It publishes original research and scientific and literature reviews on all aspects of physics. It is published by the American Physical Society. The journal is in its third series, and is split in several...
, 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., "Steady State Delay as Related to Aperiodic Signals", Bell System Technical JournalBell System Technical JournalThe Bell System Technical Journal was the in-house scientific journal of Bell Labs that was published from 1922 to 1983.- Notable papers :...
, Volume 20, Number 2, pp 222 – 234, (April 1941). - Hartley, R.V.L., "A More Symmetrical Fourier Analysis Applied to Transmission Problems," Proceedings of the IRE, 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 AmericaJournal of the Acoustical Society of AmericaJournal of the Acoustical Society of America is a scientific journal in the field of acoustics, published by the Acoustical Society of America. It contains technical articles on sound, vibration, speech and other topics.Access to articles is by subscription or purchase, though most universities...
, Volume 22, Issue 4, pg 511, (1950). - Hartley, R.V.L., "The Significance of Nonclassical Statistics", ScienceScienceScience is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...
, Volume 111, Number 2891, pp 574 – 576, (May 26, 1950) - Hartley, R.V.L., "Matter, a Mode of Motion", Bell System Technical JournalBell System Technical JournalThe Bell System Technical Journal was the in-house scientific journal of Bell Labs that was published from 1922 to 1983.- Notable papers :...
, 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 JournalBell System Technical JournalThe Bell System Technical Journal was the in-house scientific journal of Bell Labs that was published from 1922 to 1983.- Notable papers :...
, Volume 29, Number 3, pp 369 – 389, (July 1950), - Hartley, R.V.L., "A New System of Logarithmic Units", Proceedings of the IRE, Volume. 43, Number 1, pg 97, (January 1955).
- Hartley, R.V.L., "New System of Logarithmic Units", Journal of the Acoustical Society of AmericaJournal of the Acoustical Society of AmericaJournal of the Acoustical Society of America is a scientific journal in the field of acoustics, published by the Acoustical Society of America. It contains technical articles on sound, vibration, speech and other topics.Access to articles is by subscription or purchase, though most universities...
, 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 Mechanism of Gravitation", January 11, 1956, publication information unknown.
- Hartley, R.V.L., "Rotational Waves in a Turbulent Liquid", Journal of the Acoustical Society of AmericaJournal of the Acoustical Society of AmericaJournal of the Acoustical Society of America is a scientific journal in the field of acoustics, published by the Acoustical Society of America. It contains technical articles on sound, vibration, speech and other topics.Access to articles is by subscription or purchase, though most universities...
, Volume 29, Issue 2, pp 195 – 196, (1957) - Hartley, R.V.L., "A Mechanistic Theory of Extra-Atomic Physics", Philosophy of SciencePhilosophy of scienceThe philosophy of science is concerned with the assumptions, foundations, methods and implications of science. It is also concerned with the use and merit of science and sometimes overlaps metaphysics and epistemology by exploring whether scientific results are actually a study of truth...
, Volume 26, Number 4, pp 295 – 309, (October 1959)