(75 MHz). The set was in a cabin on a motor-driven platform, with a seven-element Yagi-Uda antenna mounted about five meters above the roof. The cabin, with the antenna, could be rotated over a large sector to aim the transmit-receive pattern. Detection range was 10 to 30 km for targets as low as 500 m and 25 to 100 km for high-altitude targets. Variance was about 1.5 km for range and 7 degrees for azimuth. Kharkov A second center for radio-location research was in Kharkov, Ukraine. Here the Ukrainian Institute of Physics and Technology (UIPT) closely cooperated with Kharkov University (KU). The UIPT became renowned outside the USSR, and drew visits from world-recognized physicists such as Niels Bohr and Paul Dirac. Future Nobel Laureate Lev Landau led the Theoretical Department. The independent Laboratory of Electromagnetic Oscillations (LEMO) was led by Abram A. Slutskin. At the LEMO, magnetrons were a major item of research. By 1934, a team led by Aleksandr Y. Usikov had developed a series of segmented-anode magnetrons covering 80 to 20 cm (0.37 to 1.5 GHz), with output power between 30 and 100 W. Semion Y. Braude developed a glass-cased magnetron producing 17 kW with 55 percent efficiency at 80 cm (370 MHz), tunable over a wavelength change of 30 percent, providing frequency coverage of roughly 260 MHz to 480 MHz (the boundary between VHF and UHF). These were described in detail in German-language journals – a practice adopted by the UIPT to gain publicity for their advances. In 1937, the NIIIS-KA contracted with LEMO for developing a pulsed radio-location system for aircraft detection. The project was code-named Zenit (a popular football team at the time) and was headed by Slutskin. Transmitter development was led by Usikov. The unit used a 60-cm (500-MHz) magnetron pulsed at 7–10-μs duration and providing 3-kW pulsed power, later increased to near 10 kW. Braude led receiver development. This was a superheterodyne unit initially using a tunable magnetron as the local oscillator, but this lacked stability and was replaced with a circuit using an RCA type 955 acorn triode. The returned pulses were displayed on a cathode-ray oscilloscope, giving range measurement. Zenit was tested in October 1938. In this, a medium bomber was detected at a range of 3 km, and areas for improvements were determined. After the changes had been made, a demonstration was given in September 1940. It was shown that