 A height finder MIT AN/CPS-4 Radar was added by March 9, 1950; and the station was site L-17 of the Lashup Radar Network and site LP-17 of the subsequent network during construction of the Air Defense Command permanent network.The 661st Aircraft Control and Warning Squadron was activated at Selfridge in 1951, and with a pair of General Electric AN/CPS-6 Radars, the station became site LP-20 of the permanent ADC network in 1952.In 1957 the station added a height finder General Electric AN/FPS-6 Radar.