Inter War Period
Perhaps the most significant accomplishment of the interwar period was the Signal Corps’ development of the first Army aircraft detection radar sets. These radars detected the incoming Japanese planes at Pearl Harbor, though the warnings went unheeded.
World War II
Technical contributions of the Army Signal Corps during World War II included the development and introduction of carrier equipment, spiral-four cable, facsimile equipment, frequency-modulated (FM) radios, crystal-controlled radios, microwave radar sets, and other equipment and facilities.
24 February 1944 marked the first combat use of the SCR-584 radar when the newly developed microwave gun-laying SCR-584 radar set was rushed into position near Anzio, Italy, and broke a sustained German air attack. From this time, enemy high level night bombing attacks diminished shortly.
The first use of FM multi-channel radio relay equipment in Europe was between England and the Omaha Beach in Normandy, 8 June 1944.
The most elaborate network arrangement in the history of radio broadcasting was operated by the Army Signal Corps for the release of information on the invasion of the Philippines and General Douglas MacArthur’s first official communiqué.
During the Battle of the Bulge, Army Signal Corps troops rerouted and installed more than 2,000 miles of new communication circuits in only seven days.
The peak strength of the Signal Corps was reached in June of 1944 with nearly 355,000 officers and enlisted men. This constituted 4.4 percent of the total strength of the Army.
Procurement activities expanded to multi-billion dollar proportions.
On VJ Day, 14 August 1945, the Honorable Robert P. Patterson, Under Secretary of War, wrote: “But for the great strides made in Signal Corps equipment, particularly in radar, the war would certainly not be concluded at this early date.”
Post WWII era
After WWII, the Signal Corps reverted to peacetime operations and continued its research and development programs, constantly seeking new and improved equipment with which to do its job.
Using a modified SCR-271 long range radar set, the engineers of the Army Signal Corps succeeded in making radio contact with the moon on 10 January 1946 in Project Diana.