SCR-270

radar

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Last updated

July 13, 2026

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The SCR-270 was an early radar system developed by the U.S. Army, operating at a frequency of 100 MHz. It was designed for detecting aircraft and was available at the start of World War II. One SCR-270 unit famously detected the approach of Japanese planes towards Pearl Harbor on December 7, 1941, though the significance of this detection was not fully appreciated at the time. This radar was part of a broader global effort in the 1930s to develop radar technology for military purposes, with similar initiatives occurring independently in several other countries, including Great Britain, Germany, and the Soviet Union. While early radars like the SCR-270 were crucial, advancements during the war, such as the development of microwave radars like the SCR-584, significantly improved performance and accuracy.12

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radar
First military radars
…controlling antiaircraft gunfire and the SCR-270 (at a frequency of 100 MHz) for detecting aircraft. Both of these radars were available at the start of World War II, as was the navy’s CXAM shipboard surveillance radar (at a frequency of 200 MHz). It was an SCR-270, one of six available…
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…controlling antiaircraft gunfire and the SCR-270 (at a frequency of 100 MHz) for detecting aircraft. Both of these radars were available at the start of World War II, as was the navy’s CXAM shipboard surveillance radar (at a frequency of 200 MHz). It was an SCR-270, one of six available…
Read More