Albert Hull
Encyclopedia
Albert W. Hull is most remembered for his early invention of the magnetron.
, Connecticut
. He was the son of Francis and Lewis Hull. He was the second oldest of 9 brothers, and had an older sister. Despite rural poverty all the brothers completed college, and two others, Thomas and Daniel also pursued lives devoted to science --- medicine and chemistry respectively.
He majored in Greek
and after taking one undergraduate course in physics
, graduated from Yale University
.
He taught languages at The Albany Academy
before returning to Yale, to take a doctorate in physics. He then undertook research on photoelectricity whilst teaching physics for five years at the Worcester Polytechnic Institute.
Research Laboratory (GERL) in Schenectady, New York
and remained there until his retirement in 1949.
Initially, Hull's work on these novel electron tubes was part of an effort at General Electric to develop amplifiers and oscillators that might be used to circumvent the vacuum- tube triode patents of Lee de Forest and Edwin Armstrong.
which had three electrodes: a thermionic cathode, a perforated anode, and a supplementary anode or plate. In normal operation the supplementary anode was maintained at a lower positive voltage than the perforated anode.
The secondary emission of electrons from the plate made the dynatron behave as a true negative resistance and so the tube could generate oscillations over a wide range of frequencies or be used as an amplifier. When a control grid was added between the cathode and the perforated anode, the device was called a "pliodynatron."
cylindrical anode and cathode with an axial
magnetic field produced by an external coil. The Hull magnetron was tested as an amplifier in radio receivers and also as a low-frequency oscillator. It was reported in 1925 that a magnetron made at GERL could generate a power of 15 kW at a frequency of 20 kHz. At the time Hull anticipated that the magnetron would find greater use as a power converter than in communication applications.
The Magnetron was later used by Percy Spencer to create the microwave and the British military to create radar.
s (gaseous triodes) and phanotrons (gaseous diodes).
vacuum tube which he had invented.
.
He was awarded the 1930 IEEE Morris N. Liebmann Memorial Award
and the IRE Medal of Honor
in 1958 by the Institute of Radio Engineers
(IRE) "For outstanding scientific achievement and pioneering inventions and development in the field of electron tubes."
He did consulting work and served on an advisory committee of the Army Ballistics Research Laboratories after retirement from General Electric and was elected a member of the National Academy of Sciences. He also served as president of the American Physical Society in 1942.
He died on 22 January 1966 at the age of 85.
Education and early career
Albert Wallace Hull was born on a farm in SouthingtonSouthington, Connecticut
Southington is a town in Hartford County, Connecticut, United States. It is part of Connecticut's 1st congressional district. It is situated about 20 miles southwest of Hartford, about 80 miles northeast of New York City, 105 miles southwest of Boston and 77 miles west of Providence...
, Connecticut
Connecticut
Connecticut is a state in the New England region of the northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, and the state of New York to the west and the south .Connecticut is named for the Connecticut River, the major U.S. river that approximately...
. He was the son of Francis and Lewis Hull. He was the second oldest of 9 brothers, and had an older sister. Despite rural poverty all the brothers completed college, and two others, Thomas and Daniel also pursued lives devoted to science --- medicine and chemistry respectively.
He majored in Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
and after taking one undergraduate course in physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
, graduated from Yale University
Yale University
Yale University is a private, Ivy League university located in New Haven, Connecticut, United States. Founded in 1701 in the Colony of Connecticut, the university is the third-oldest institution of higher education in the United States...
.
He taught languages at The Albany Academy
The Albany Academy
The Albany Academy is an independent college preparatory day school for boys in Albany, New York, USA, enrolling students from Preschool to Grade 12. It was established in 1813 by a charter signed by Mayor Philip Schuyler Van Rensselaer and the city council of Albany...
before returning to Yale, to take a doctorate in physics. He then undertook research on photoelectricity whilst teaching physics for five years at the Worcester Polytechnic Institute.
Industry
In 1914 Hull joined the General ElectricGeneral Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
Research Laboratory (GERL) in Schenectady, New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
and remained there until his retirement in 1949.
Experimental work
During 1916, Hull began investigation into the use of magnetic control of thermionic valves (vacuum tubes) as an alternative to grid or electrostatic control and he had tested successfully magnetic control by applying a magnetic field parallel to the axis of the tube.Initially, Hull's work on these novel electron tubes was part of an effort at General Electric to develop amplifiers and oscillators that might be used to circumvent the vacuum- tube triode patents of Lee de Forest and Edwin Armstrong.
Dynatron
He invented the dynatronDynatron
For the brand, see Dynatron Radio LtdThe dedicated dynatron vacuum tube was invented by Albert Hull in 1918. It has three electrodes: a thermionic cathode, a perforated anode, and a supplementary anode or plate, and its characteristic curves have a region exhibiting negative resistance, which is...
which had three electrodes: a thermionic cathode, a perforated anode, and a supplementary anode or plate. In normal operation the supplementary anode was maintained at a lower positive voltage than the perforated anode.
The secondary emission of electrons from the plate made the dynatron behave as a true negative resistance and so the tube could generate oscillations over a wide range of frequencies or be used as an amplifier. When a control grid was added between the cathode and the perforated anode, the device was called a "pliodynatron."
Magnetron
By 1920 his research led to his invention of the magnetron. This took the form of a coaxialCoaxial
In geometry, coaxial means that two or more forms share a common axis; it is the three-dimensional linear analogue of concentric.Coaxial cable, as a common example, has a wire conductor in the centre a circumferential outer conductor and an insulating medium called the dielectric separating...
cylindrical anode and cathode with an axial
Axial
Axial may mean:* Along the same line as an axis of rotation in geometry* A type of modal frame in music* One of several anatomical directions in an animal body* Axial age, the period from 800 to 200 BC in China, India and the western world...
magnetic field produced by an external coil. The Hull magnetron was tested as an amplifier in radio receivers and also as a low-frequency oscillator. It was reported in 1925 that a magnetron made at GERL could generate a power of 15 kW at a frequency of 20 kHz. At the time Hull anticipated that the magnetron would find greater use as a power converter than in communication applications.
The Magnetron was later used by Percy Spencer to create the microwave and the British military to create radar.
Gas-filled electron tubes
During the 1920s, Hull also was a major contributor to the development of gas-filled electron tubes at the GERL. He discovered how to protect thermionic cathodes from rapid disintegration under ion bombardment. This discovery enabled the successful development of hot-cathode thyratronThyratron
A thyratron is a type of gas filled tube used as a high energy electrical switch and controlled rectifier. Triode, tetrode and pentode variations of the thyratron have been manufactured in the past, though most are of the triode design...
s (gaseous triodes) and phanotrons (gaseous diodes).
Publications
In the 1918 issue of the Proceedings of the IRE he published a paper on the dynatronDynatron
For the brand, see Dynatron Radio LtdThe dedicated dynatron vacuum tube was invented by Albert Hull in 1918. It has three electrodes: a thermionic cathode, a perforated anode, and a supplementary anode or plate, and its characteristic curves have a region exhibiting negative resistance, which is...
vacuum tube which he had invented.
Career promotion
Hull was promoted to assistant director of the GERL in 1928 and was known for his collegial management style with minimal interference with the research agenda of his staff members.Awards
He was awarded the 1924 Howard N. Potts Medal of the Franklin InstituteFranklin Institute
The Franklin Institute is a museum in Philadelphia, Pennsylvania, and one of the oldest centers of science education and development in the United States, dating to 1824. The Institute also houses the Benjamin Franklin National Memorial.-History:On February 5, 1824, Samuel Vaughn Merrick and...
.
He was awarded the 1930 IEEE Morris N. Liebmann Memorial Award
IEEE Morris N. Liebmann Memorial Award
The initially called Morris Liebmann Memorial Prize provided by the Institute of Radio Engineers , the IEEE Morris N. Liebmann Memorial Award was created in 1919 in honor of Colonel Morris N. Liebmann. It was initially given to awardees who had "made public during the recent past an important...
and the IRE Medal of Honor
IEEE Medal of Honor
The 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...
in 1958 by the Institute of Radio Engineers
Institute of Radio Engineers
The 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...
(IRE) "For outstanding scientific achievement and pioneering inventions and development in the field of electron tubes."
He did consulting work and served on an advisory committee of the Army Ballistics Research Laboratories after retirement from General Electric and was elected a member of the National Academy of Sciences. He also served as president of the American Physical Society in 1942.
He died on 22 January 1966 at the age of 85.