Oskar Heil
Encyclopedia
Oskar Heil was a German
electrical engineer and inventor. He studied physics
, chemistry
, mathematics
, and music
at the Georg-August University of Göttingen and was awarded his PhD
in 1933, for his work on molecular spectroscopy.
, the Soviet Union
in 1934. Together they moved to the United Kingdom
to work in the Cavendish Laboratory
, University of Cambridge. While on a trip to Italy, they co-wrote a pioneering paper on the generation of microwaves which was published in Germany in 1935. Agnesa subsequently returned to Russia to pursue this work further at the Leningrad Physico-Chemical Institute with her husband. However, he then returned to the UK alone; Agnesa, working in what had by then become a highly-sensitive subject, was possibly not allowed to leave. Back in Britain, Oskar Heil worked for Standard Telephones and Cables until the onset of the Second World War
, when he returned to Germany via Switzerland. After the war ended, he went to work in the United States and eventually died there in 1994. Agnesa remained in the Soviet Union until she died in 1991.
and subsequently the reflex klystron based on the same operating principle. These devices were a significant milestone in the development of microwave technology (particularly radar
), and velocity-modulated tubes are still very much in use at the present day.
-like device (see also History of the transistor
), based on several patents that were issued to him.
JFETS: The New Frontier states:
The Heil diaphragm is made of Mylar bonded with conductive aluminum strips. It is equivalent in surface area to a conventional eight-inch cone-type midrange driver, but is accordion-folded down to a compact one-inch band for better point-source dispersion. The low-mass diaphragm is suspended within a massive magnet concentrating an intense magnetic field around the diaphragm. When a signal current passes through the aluminum strips, the ensuing bellows-like motion of the folded "pleats" squeezes air out five times faster than with a conventional cone driver. This rapid acceleration of the air is claimed to provide enhanced sound reproduction, including high dynamic range.
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
electrical engineer and inventor. He studied 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...
, chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
, mathematics
Mathematics
Mathematics is the study of quantity, space, structure, and change. Mathematicians seek out patterns and formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proofs, which are arguments sufficient to convince other mathematicians of their validity...
, and music
Music
Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...
at the Georg-August University of Göttingen and was awarded his PhD
Doctor of Philosophy
Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil , in English-speaking countries, is a postgraduate academic degree awarded by universities...
in 1933, for his work on molecular spectroscopy.
Personal life
At the Georg-August University in Göttingen, Oskar Heil met Agnesa Arsenjewa (1901–1991), a promising young Russian physicist who also earned her PhD there. They married in LeningradLeningrad
Leningrad is the former name of Saint Petersburg, Russia.Leningrad may also refer to:- Places :* Leningrad Oblast, a federal subject of Russia, around Saint Petersburg* Leningrad, Tajikistan, capital of Muminobod district in Khatlon Province...
, the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
in 1934. Together they moved to the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
to work in the Cavendish Laboratory
Cavendish Laboratory
The Cavendish Laboratory is the Department of Physics at the University of Cambridge, and is part of the university's School of Physical Sciences. It was opened in 1874 as a teaching laboratory....
, University of Cambridge. While on a trip to Italy, they co-wrote a pioneering paper on the generation of microwaves which was published in Germany in 1935. Agnesa subsequently returned to Russia to pursue this work further at the Leningrad Physico-Chemical Institute with her husband. However, he then returned to the UK alone; Agnesa, working in what had by then become a highly-sensitive subject, was possibly not allowed to leave. Back in Britain, Oskar Heil worked for Standard Telephones and Cables until the onset of the Second World War
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...
, when he returned to Germany via Switzerland. After the war ended, he went to work in the United States and eventually died there in 1994. Agnesa remained in the Soviet Union until she died in 1991.
Microwave vacuum tube
Oskar Heil and Agnesa Arsenjewa-Heil in their pioneering paper developed the concept of the velocity-modulated tube, in which a beam of electrons could be made to form into "bunches" and thereby generate with reasonable efficiency radio waves of considerably higher frequency and power than were possible with conventional vacuum tubes/thermionic valves. This resulted in production of the "Heil tube", the first truly-practicable microwave generator, which slightly predated the (independent) invention of the klystronKlystron
A klystron is a specialized linear-beam vacuum tube . Klystrons are used as amplifiers at microwave and radio frequencies to produce both low-power reference signals for superheterodyne radar receivers and to produce high-power carrier waves for communications and the driving force for modern...
and subsequently the reflex klystron based on the same operating principle. These devices were a significant milestone in the development of microwave technology (particularly radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
), and velocity-modulated tubes are still very much in use at the present day.
Field-effect transistor
Heil is sometimes mentioned as an inventor of an early transistorTransistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...
-like device (see also History of the transistor
History of the transistor
-Invention of the transistor:The first patent for the field-effect transistor principle was filed in Canada by Austrian-Hungarian physicist Julius Edgar Lilienfeld on October 22, 1925, but Lilienfeld published no research articles about his devices, and they were ignored by industry. In 1934 German...
), based on several patents that were issued to him.
JFETS: The New Frontier states:
- "Field-effect transistors (FETs) have been around for a long time; in fact, they were invented, at least theoretically, before the bipolar transistors. The basic principle of the FET has been known since J.E. LilienfeldJulius Edgar LilienfeldJulius Edgar Lilienfeld was an Austro-Hungarian physicist. He was born in Lemberg in Austria-Hungary , moved to the United States in the early 1920s, and became American citizen in 1934...
’s US patent from 1930, and Oscar Heil described the possibility of controlling the resistance in a semiconducting material with an electric field in a British patent in 1935."
Air Motion Transformer
He also invented the "Heil air motion transformer" audio speaker technology made famous by the AMT-1A speakers of ESS Labs in the mid 1970s.The Heil diaphragm is made of Mylar bonded with conductive aluminum strips. It is equivalent in surface area to a conventional eight-inch cone-type midrange driver, but is accordion-folded down to a compact one-inch band for better point-source dispersion. The low-mass diaphragm is suspended within a massive magnet concentrating an intense magnetic field around the diaphragm. When a signal current passes through the aluminum strips, the ensuing bellows-like motion of the folded "pleats" squeezes air out five times faster than with a conventional cone driver. This rapid acceleration of the air is claimed to provide enhanced sound reproduction, including high dynamic range.