Otto Scheller

from Wikipedia, the free encyclopedia
Otto Scheller (around 1926)

Otto Scheller (born June 6, 1876 in Blankenstein , † April 14, 1948 in Berlin ) was a German electrical engineer and inventor .

Otto Scheller was a pioneer of early radio technology. Its contribution to radio navigation is still the basis of numerous systems today. His idea, patented as early as 1907 while working for C. Lorenz AG, was ahead of its time. It was only taken up again in the 1920s and was also successfully used commercially by Ernst Ludwig Kramar from 1930 when he was developing the first instrument landing systems.

Life

Otto Scheller grew up in Eisenach and attended the secondary school there. He then studied mechanics and electrical engineering at the Königlich Technische Hochschule Charlottenburg . The then university director and well-known scientist in early wireless transmission, Adolf Slaby, aroused his interest in radio technology, which was the focus of his later scientific life. He began his professional life as an engineer at the Allgemeine Electricitäts-Gesellschaft (AEG) with the design and construction of the first commercial radio transmitters in the German Reich . On behalf of the AEG subsidiary Telefunken , shortly after its establishment in 1903, he traveled to Mexico and the United States to install the first transmitters there, including a system for the United States Navy in Annapolis , Maryland .

In 1906 Scheller worked as a manager at the Amalgamated Radio Telegraph Company Ltd. founded by the inventor Valdemar Poulsen . in London. He worked on the practical implementation and improvement of the invention with which Poulsen succeeded in 1903 in generating stable high-frequency radio waves using an arc transmitter . Around this time, the Berliner Aktiengesellschaft C. Lorenz acquired a license to use the patents in Germany. Otto Scheller switched to C. Lorenz in Berlin and continued his work with Walter Hahnemann . In 1907 Scheller received a patent to improve the arc lamp. This relies on liquid hydrogen compounds to generate rapid vibrations, which are introduced into the vessel that surrounds the arc burning in a magnetic field and evaporated in it. The arrangement of the components, which was optimized by Scheller and his colleague Hans Rein, was one of the decisive factors that enabled C. Lorenz to develop over several years with the arc transmitter from 1908 onwards to become a serious competitor for the Telefunken in supplying the German Army and the Imperial Navy with radio technology .

As early as March 17, 1907, just a little more than three years after the Wright brothers had successfully carried out the first powered flight in Kitty Hawk , he was granted patent no. 201496 under the title "Wireless Course Guide and Telegraph". In it he described a system of two directional transmitters with the same intensity and wavelength, which are at an angle to each other and send alternately. Initially, the patent was largely ignored. Scheller was too far ahead of his time and developments in both aviation and radio technology. It was not until about ten years later that a first transmitting station based on this principle was successfully tested by Franz Kiebitz for the Imperial Navy. At the beginning of his work, Kiebitz was probably not even aware of Scheller's preliminary work. On January 9, 1916, Scheller received another patent based on his preparatory work from 1907 under No. 299753. He transferred his original idea to a device arrangement that expanded his system with the function of a goniometer . On the basis of his idea, C. Lorenz developed the Lorenz landing procedure under the direction of the engineer Ernst Ludwig Kramar from 1932 and installed the necessary radio systems at 38 airports in the German Reich and internationally by 1938 . The instrument landing system (ILS) introduced worldwide after the Second World War is based on the same basis .

In 1911 Otto Scheller became technical manager of the radio department at C. Lorenz . In the following years he made numerous contributions on a very wide range of topics in the field of radio technology. He worked on the high-frequency telegraph developed by Rudolf Goldschmidt , dealt with radio frequency measurement, antenna design, electro-acoustics and the first basics for later television.

As an engineer, he was also involved in the construction of the radio station at the Herzogstand in the Bavarian Alps , where two neighboring mountain peaks were used to stretch an approximately 2.5 km long antenna for radio traffic over the valley on long waves .

Scheller retired in 1924, but still made other scientific contributions. Finally he developed an interest in the use of wind energy and received several patents in this area. He died on April 15, 1948 at the age of 71 in Berlin.

Services

Between 1907 and 1940 he received 110 patents and was posthumously honored by the IEEE Professional Technical Group on Aerospace and Navigational Electronics with the Pioneer Award of 1966 in order not to be forgotten, to whom the now well-known fundamentals are due.

Fig. 2 - from patent specification No. 201496 from 1907

With the description in his patent from 1907, he formulated a radio technology principle for generating orientation lines, which is still one of the essential foundations of navigation systems today:

"The invention now defines such lines in that two directional transmitters of the same intensity and wavelength A 1 -A 2 and B 1 -B 2 are at an angle to each other and alternately send out characters.

If the angle is chosen correctly, the line of the same intensity is easy to see for moving stations and very sharp. Sends z. B. the transmitter A 1 -A 2 short, the transmitter B 1 -B 2 longer strokes, in such a way that always one or the other transmitter emits, so you will be on a moving station that crosses the line of the same intensity , when receiving the telephone, only perceive a steady noise, which, however, immediately breaks down into individual signs of different intensity if one moves away from the marking line. Depending on whether one or the other type of sign becomes stronger, you can at the same time, since you will generally know in which direction you have to look for the transmitter station, on which side of the marking line you are. "

- Otto Scheller : Wireless course guide and telegraph , patented in the German Reich, No. 201496

Works

  • Aircraft control in poor weather . In: Elektrotechnische Zeitschrift , year 1929, No. 50. P. 191 f.
  • The construction of the mountain antenna at the Herzogstand . In: Elektro Nachrichten-Technik , Volume 3, Issue 7, July 1926.

literature

Individual evidence

  1. ↑ German Reich Patent No. 201626: Arc lamp for generating rapid electrical oscillations from August 14, 1907.
  2. ↑ Abraham Esau: Wireless Bearing . In: Telefunken Zeitung , Volume IV, No. 22, March 1921. Ed .: Society for wireless telegraphy mbH ( Telefunken ). P. 4
    ( online version , digitized 11/2009 by Thomas Günzel for www.radiomuseum.org )
  3. ↑ Fritz Schröter (Ed.): Handbook of picture telegraphy and television . Verlag von Julius Springer 1932. p. 73
    ( limited preview in Google book search)
  4. ^ Wilhelm Herbst: Bergantnen: Herzogstand (Bavaria) and Malabar (Java) 1920–1927 , Wilhelm Herbst Verlag 2014. ISBN 978-3-923925-83-4
  5. ^ Institute of Electrical and Electronics Engineers : Pioneer Awards (PDF; 5.2 MB), July 1966. In: IEEE.org, accessed October 26, 2015
personal data
SURNAME Scheller, Otto
BRIEF DESCRIPTION German electrical engineer
DATE OF BIRTH June 6, 1876
PLACE OF BIRTH Blankenstein
DATE OF DEATH April 14, 1948
Place of death Berlin