August Žáček

August Žáček (born January 13, 1886 in Dobšice ; † 1961 ) was a Czech physicist.

He studied in České Budějovice and then at the philosophical department of Charles University in Prague with Professors F. Koláček and B. Kučera and then, until shortly before the outbreak of World War I, at the University of Göttingen with Hermann Theodor Simon (1870-1918 ) at the Institute for Applied Electricity in the field of electrical vibrations.

During the First World War he tried with limited success, together with Professor František Záviška, to verify some of the results of his theory on the diffraction of electromagnetic waves on parallel, round cylinders by damped oscillations.

He realized that undamped vibrations, stimulated by electron tubes, should be used. This was the basis of his later work after the war: About a DC amplifier, electron tubes in radio telegraphy, About the use of electron tubes in experiments with singing arcs and singing capacitors, About the calibration of a wavemeter in the magazine Casopis pro pestování matematiky a fysiky . The most important was A new method for producing undamped oscillations (1924, Ed. 53, p. 378) in which he developed a new method for very short electromagnetic waves from a patented magnetron (registered: May 31, 1924, granted: February 15 1926, CZ patent no .: 20.293). Since there was no foreign edition of the journal, its invention remained unknown. It was rediscovered by the Soviet scientists Abram Sluzkin and Dmitri S. Steinberg (Proceedings of the Ukrainian Academy of Sciences 1 (1927), 22; Ann. D. Phys. 1 (1929), 658) and Professor Yagi Hidetsugu (Prec. Of the Inst. of Radio Eng. 16 (1928), 729). He then decided to publish his method in the yearbook of wireless telegraphy and telephony (Ztschr. F. Hochfrequenztechnik; 32 (1928), 172) and to defend his priority.

Publications

• Elektronové lampy a jich užití v radiotelegrafii. 1921
• About the use of electron tubes in the experiments with the speaking arc and the speaking capacitor. In: Physikalische Zeitschrift. Volume 22, 1921, pp. 528-529
• with Manne Siegbahn : About the relative intensity of the K lines. In: Chemisches Zentralblatt. 1923
• with Václav Petržílka: Klínové piezoelektrické resonátory. 1935
• Magnetronové generátory. 1936

literature

• RH Fürth: Obituary: Prof. August Žáček. In: Nature. Volume 193, 1962, No. 4816, p. 625
• The 70th birthday of Prof. Dr. August Žáček. In: Czechoslovak Journal of Physics. Volume 6, No. 2, 1956, pp. 204–205 ( doi: 10.1007 / BF01699894 )

Web links

• Literature and other media by and about August Žáček in the catalog of the National Library of the Czech Republic