The Sperry Gyroscope Company developed the radar and computer, and development of what would become the Skysweeper started in 1948. A new 75 mm gun, known as the T83E1 or M35, was developed that had excellent muzzle velocity, along with two ten-round revolver-type magazines and an auto-loader that allowed it to reach 45 rounds/minute—about one third of what the much lighter Bofors had managed. This was mounted on a large square platform with powered traverse, which also mounted the box-shaped computer and manual gunsights on the right side, and the T-38 radar unit on the left. The T-38 radar had a range of about 30 km and could track aircraft traveling at up to 700 mph (1100 km/h).