Russell and Sigurd Varian

Russell Harrison Varian ( born April 24, 1898 in Washington, DC; † July 28, 1959 in Juneau, Alaska) was an American scientist and inventor of a microwave generator and magnetometer.

Life

Russell was of Irish descent and had a younger brother, Sigurd Varian Fergus ( born May 4, 1901 in Syracuse (New York) Syracuse, New York; † 18 October 1961, in Puerto Vallarta, Mexico) was the commercial pilot for Pan Am. He graduated from Stanford University in 1927 and earned his master's degree. Here also studied 1925-33 William Webster Hansen, who conducted research later on cavity resonators. He then worked for various companies, such as Philo Farnsworth Television Company and Humble Oil and Refining Co., of instruments for oil production.

When his brother of his bad experience of flying at night and in fog reported and looked for possibilities of all-weather navigation, Russell sought after methods, even flying airplanes in bad weather and at night to be able to locate. The article from the year 1935 by Agnessa and Oskar Heil him was as unknown as the secret military research with pulsed RF signals, later radar.

It took radio waves can penetrate the clouds, of such short wavelength that they achieve the required resolution. The RF amplifiers then in use had a too low upper frequency limit. Firstly, have resonant circuits with concentrated capacitances and Induktiväten or Lecher lines in the microwave region of very high radiation losses. On the other hand with density controlled electron tubes, the upper frequency limit is determined by the inner tube capacity, the lead inductances of the electrodes and the electron- running time. The wavelength with the ever decreasing density controlled electron tubes allowed only small anode power losses. So had in March 1935 brought out by RCA DeForest acorn tube ( 955 Acorn triode) at an RF power of 0.5 W is a cutoff wavelength of 100 cm.

After Varian had learned of Hansen's work on cavity resonators, the brothers traveled on March 5, 1937 Hansen. On the one hand they wanted to obtain his permission to use the resonator and discuss the other to him about the Farnsworth multipactor, a dynamic secondary electron multiplier, from which they hoped that this would be useful as a microwave amplifier. Hansen just tested his resonator, which his student called Rhumba, from which later developed into the name Rhumbatron. On March 30, Sigurd struck Stanford University before a contract, using the devices of the physical faculty, and may at any time ask Bill Hansen and other scientists for advice. The profit should be divided equally between the University, Russell and Sigurd. Hansen took the time to examine Russell's theories and to formulate mathematically. On June 5, 1937 Russell thought about a speed grouping principle, which he called bunching (Alfred Recknagel and Ernst breaks it designated 1938 as phase focusing). They tested the idea of ​​using the term of the electrons as a function principle, and decided to develop a two-chamber Rhumbatron oscillator for 10 cm wavelength, which swung been stable on 30 August 1937. On October 11, 1937, she reported to her patent. Your microwave generator they described later as a two- cavity klystron, because the velocity modulation served a double grating, which lay on each at the same potential with two walls of a cavity. The klystron in the centimeter wavelength range was used in the construction of microwave links. After the operation was explored in all its details, the team of development is still lacking measuring method applied for wavelength, frequency, power and impedance to.

1948, the brothers founded the company Varian Associates for the production of klystrons, especially those of very high performance for the radar equipment and television stations. Varian developed for the Vanguard Project 1957, a magnetometer to measure the earth's magnetic field. Varian received approximately 100 patents in the field of microwave technology. In 1995, the klystron and radar technology was spun off and is now called Communications & Power Industries, CPI. Varian Associates in 1999 to split into three parts - Varian, Inc. ( since 2010 part of Agilent Technologies), and Varian Medical Varian Semiconductor (owned since 2011 to Applied Materials ).