This collection includes historic radar units such as the SCR 270B, the "Pearl Harbor" unit that first detected the hoard of Japanese planes headed toward Pearl Harbor in 1941. The SCR 270B is accompanied by its operations van and the power van. Also included in this collection is the SCrR 270D, a later model which is on exhibit at the National Electronic Museum in Linthicum, MD. Other historical radar units will be added later.