to General der Luftnachrichtentruppe (General of the Air Signal Corps) and remained in this position until the end of the war in May 1945. All three branches of the combined Wehrmacht armed forces of Nazi Germany: the Luftwaffe (Air Force), the Kriegsmarine (Navy), and the Heer (Army); used German radar technology and hardware. Although a number of development laboratories were operated by these users, the vast majority of radars were supplied by four commercial firms: GEMA, Telefunken, Lorenz, and Siemens & Halske. Near the end of the war in 1945, GEMA led the German radar work, growing to over 6,000 employees. The official designation of radar systems was FuMG (Funkmessgerät, literally "Radio measuring device"), with most also with a letter (e.g., G, T, L, or S) indicating the manufacturer, as well as a number showing the year of release and possibly a letter or number giving the model. There was, however, a lack of uniformity in designations. Ground and ship-based In early 1938, the Kriegsmarine funded GEMA for the development of two systems, one a gun-laying set and the other an air-warning set. In production, the first type became the 80-cm (380-MHz) Flakleit, capable of directing fire on surface or air targets within an 80-km range. It had an antenna configuration very similar to the U.S. SCR-268. The fixed-position version, the Flakleit-G, included a height-finder. The second type developed by GEMA was the 2.5 m (120 MHz) Seetakt. Throughout the war, GEMA provided a wide variety of Seetakt sets, mainly for ships but also for several types for U-boats. Most had an excellent range-measuring module called Messkette (measuring chain) that provided range accuracy within a few meters regardless of the total range. The shipboard Seetakt used a "mattress" antenna similar to the "bedspring" on the American CXAM. Although the Kriegsmarine attempted to keep the GEMA from working with the other services, the Luftwaffe became aware of the Seetakt and ordered their own version in late 1938. Called the Freya, this was a ground-based radar operating around 2.4 m (125 MHz) with 15-kW peak power giving a range of some 130 km. The basic Freya radar was continuously improved, with over 1,000 systems eventually built. In 1940, Josef Kammhuber used Freyas in a new air-defense network extending through the Netherlands, Belgium, and France. Called the Kammhuber Line by the Allies, it was composed of a series of cells code-named Himmelbett (four-poster