Germany. For this function, consultants Theodor Schultes and Hans Hollmann designed an experimental 2.4-m (125-MHz), 30-kW radar called Panorama. Built by Siemens & Halske in 1941, it was placed atop a concrete tower at Tremmen, a few kilometers south of Berlin. The antenna had 18 dipoles on a long, horizontal support and produced a narrow vertical beam; this rotated at 6 rpm to sweep out 360-degrees of coverage to about 110 km. Based on the operation of Panorama, Siemens & Halske improved this system, and renamed it Jagdschloss (hunting lodge). They added a second switchable operation to 150 kW at 1.2 m (250 MHz), increasing the range to near 200 km. The information from the receivers was sent via co-axial cable or a 50-cm link from the tower to a central command center, where it was used to direct fighter aircraft. Hollmann's polar-coordinate (PPI) CRT was used in the display, the first German system with this device; it was also added to the Panorama. The Jagdschloss entered service in late 1943, and about 80 systems were eventually built. The Jagdwagen (hunting car) was a mobile, single-frequency version; operating at 54 cm (560 MHz), it had a correspondingly smaller antenna system. Under an internally funded project, the firm Lorenz AG developed a pulse-modulated set. The Heer contracted for a few sets for Flak (anti-aircraft) support, but then this mission was transferred to the Luftwaffe. Over several years, Lorenz was unsuccessful in selling new versions called Kurfürst and Kurmark (both Holy Roman Imperial terms). As the war continued, a need was seen by the Luftwaffe for additional radars. Lorenz again modified their sets to become the Tiefentwiel, a transportable system built to complement the Freya against low-flying aircraft, and the Jagdwagen, a mobile unit used for air surveillance. These 54-cm (560-MHz) units with plan-position indicators, had two antennas backed by parabolic, mesh reflectors on rotatable, forked frames that lifted above the equipment cabin. Starting in 1944, both of these systems were produced by Lorenz for the Luftwaffe in relatively small numbers. Although German researchers had developed magnetrons in the early 1930s (Hans Hollmann received a U.S. patent on his device in July 1938), none had been suitable for military radars. In February 1943, a British bomber containing a H2S radar was shot down over the Netherlands, and the 10-cm magnetron was found intact. In short order, the secret of making successful magnetrons