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A History of Microwave Ovens
Some humans put a ~2.4GHz magnetron on a ventilated metal box with a fancy door.
But Raytheon's basic idea was simple: put food in a Faraday cage and blast it with 2.4 GHz radio waves to spin the water molecules. Such ranges were attractive to consumers since both microwave energy and conventional heating elements could be used simultaneously to speed cooking, and there was no loss of countertop space. The source (oscillator) energy is then amplified using Laterally Diffused Metal Oxide Semiconductor (LDMOS) technology to a level of approximately 300 watts (54.8 dBm).
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