OLLENDORFF, FRANZ (1900–1981), Israeli engineer. Born in Berlin, Ollendorff in 1924 joined the Siemens research department in Berlin, working under Reinhold Ruedenberg. From 1928 he taught in the engineering faculty of the Berlin Technische Hochschule. After being dismissed from his post by the Nazis in 1933, he joined the teaching staff of the Jewish public school in Berlin, moving to Jerusalem when the school and staff transferred there in 1934. Ollendorff returned to Germany in the following year to organize the transfer of Jewish children to Ereẓ Israel within the framework of the newly established Youth Aliyah. In 1937 he was finally expelled by the Gestapo and, on his return to Palestine, joined the staff of the Haifa Technion. Ollendorff was a professor there from 1939. He became research professor in the faculty of electrical engineering and worked in the field of biomedical electronics and physics. He was a member of the Israel Academy of Science and was awarded the Israel Prize for his research in magnetic fields (1954). He was elected a fellow of the American Institute of Electrical Engineers in 1963 and served as the Institute's vice president. His interest in the education of teenagers made him a keen supporter of the Technion's vocational high school. Ollendorff wrote books and papers on electronics, physics, mathematics, acoustics, medical electronics, technical education, and other specialized fields. His publications include Die Grundlagen der Hochfrequenztechnik (1926); Erdstroeme (1928); Die Welt der Vektoren (1950); and Innere Elektronik (1955).