Jonathan Adolf Wilhelm Zenneck (April 15, 1871 - April 8, 1959) was a physicist and electrical engineer. Zenneck was born in Ruppertshofen, Württemberg. Zenneck contributed to researches in radio circuit performance and to the scientific and educational contributions to the literature of the pioneer radio art. Zenneck improved the Braun cathode ray tube, by adding a second deflection structure at right angles to the first, which allowed two-dimensional viewing of a waveform. This two-dimensional display is fundamental to the oscilloscope.^[2]

  Early years

In 1885, Zenneck entered the Evangelical-Theological Seminary in Maulbronn. In 1887, in a Blaubeuren seminary, Zenneck learned Latin, Greek, French, and Hebrew. In 1889, Zenneck enrolled in the Tübingen University. At the Tuebingen Seminary, Zenneck studied mathematics and natural sciences. In 1894, Zenneck took the State examination in mathematics and natural sciences and the examination for his doctor's degree.

In 1894, Zenneck conducted zoological research (Natural History Museum, London). Between 1894-1895, Zenneck served in the military.

  Middle years

1895 Zenneck left zoology and turned over to the new field of radio science, He became assistant to Ferdinand Braun and lecturer at "Physikalisches Institut" in Strasbourg, Alsace. Nikola Tesla lectures introduced him to the wireless sciences. In 1899, Zenneck started propagation studies of wireless telegraphy, first over land, but then became more interested in the larger ranges that were reached over sea. In 1900 he started ship-to-coast experiments in the Northern Sea near Cuxhaven, Germany. in 1902 he conducted tests of directional antennas. In 1905, Zenneck left Strasbourg since he was appointed assistant-professor at the Danzig Technische Hochschule and in 1906, he was became professor of experimental physics in the Braunschweig Technische Hochschule. Also in 1906, Zenneck wrote "Electromagnetic Oscillations and Wireless Telegraphy", the then standard textbook on the subject). In 1909, he joined Badische Anilin und Sodafabrik in Ludwigshafen to experiment with electrical discharges in air to produce bound nitrogen as fertilizer.

  Memorial in Cuxhaven

  Later years

Around World War I, Zenneck went to the front as a Captain in the Marines. However, in 1914, the German government sent him to the United States as technical advisor in a patent case of great importance to Germany. When the United States entered the war they declared Zenneck a Prisoner of War. He was dismissed only in 1920 when he could finally take over the professorship of experimental physics at the Technische Hochschule in Munich. In that time he resumed propagation studies, now with shortwaves and was first in Germany to study the Ionosphere with vertical sounding at his station at Kochel/Bavaria. Since the 1930s Zenneck directed the Deutsche Museum in Munich and rebuilt it after World War II. Zenneck was awarded the 1928 IRE Medal of Honor for his achievements in basic research on radio technology and for fostering academic and technical offspring he received the Siemens-Ring in 1956.

  See also

• Kugelbake
• Spread spectrum

  References

• Jonathan Zenneck (1871–1959)
• Physik Departments an der Technischen Universität München, "Booklet". Chapter 11. History (PDF)
• IEEE History Center - "Legacies: Jonathan A. Zenneck"
• Zenneck, J. (1901). "Gravitation" (in German). Encyklopädie der mathematischen Wissenschaften mit Einschluss ihrer Anwendungen 5: 25–67. http://dz-srv1.sub.uni-goettingen.de/sub/digbib/loader?did=D189514.