BBC tells the story of the magnetron which stunned the Americans. Their research was years off the pace.
President Roosevelt approved funds for a new laboratory at Massachusetts Institute of Technology administered not by the military but a civilian agency.
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By any measure, MIT's Radiation Laboratory - known as the Rad Lab - was a resounding success. It spawned 10 Nobel laureates. The radar it developed, detecting planes and submarines, helped to win the War.
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The story captured my attention having memories learning basic electronics in high school but being dumbfounded by the simplicity of the magnetron my brother picked up at an army surplus store. wikipedia
MIT Radiation Lab
I was also charmed by the people side of the story. I started my career in a research lab at a company who's founder worked on WWII radar and went on to build the first commercial calibrated oscilloscopes suitable for quantitative measurements. See Tektronix
Home Electronics Lab
I was also struck to see a familiar instrument among all of the equipment assembled for the radar research. There in a photo from the era was a volt-ohm-milliammeter at the center of a workbench. I own a Simpson 260 Series 5 meter. I bought the professional instrument as I entered college and still bring it out occasionally. page
Most recently I used my Simpson to observe the digital filtering response characteristics of an adaptive sensor realized in an Arduino with no other convenient output. It worked so well I bought a bunch of surplus meters and built an array to watch all the variables at once. post
I'm quick to point out to visitors of the Computer History Museum that those are Tektronix oscilloscopes in the background where engineers were building the first computers. Simpson deserves similar credit.