Microwave oven
In 1947, Raytheon built the "Radarange", the first commercially available microwave oven. It was almost tall, weighed and cost about US$5,000 ($ in dollars) each. It consumed 3 kilowatts, about three times as much as today's microwave ovens, and was water-cooled. The name was the winning entry in an employee contest. An early Radarange was installed (and remains) in the galley of the nuclear-powered passenger/cargo ship NS "Savannah". An early commercial model introduced in 1954 consumed 1.6 kilowatts and sold for US$2,000 to US$3,000 ($ to $ in dollars). Raytheon licensed its technology to the Tappan Stove company of Mansfield, Ohio in 1952. They tried to market a large 220 volt wall unit as a home microwave oven in 1955 for a price of US$1,295 ($ in dollars), but it did not sell well.
Microwave oven
In 1945, the specific heating effect of a high-power microwave beam was accidentally discovered by Percy Spencer, an American self-taught engineer from Howland, Maine. Employed by Raytheon at the time, he noticed that microwaves from an active radar set he was working on started to melt a chocolate bar he had in his pocket. The first food deliberately cooked with Spencer's microwave was popcorn, and the second was an egg, which exploded in the face of one of the experimenters. To verify his finding, Spencer created a high density electromagnetic field by feeding microwave power from a magnetron into a metal box from which it had no way to escape. When food was placed in the box with the microwave energy, the temperature of the food rose rapidly. On 8 October 1945, Raytheon filed a United States patent application for Spencer's microwave cooking process, and an oven that heated food using microwave energy from a magnetron was soon placed in a Boston restaurant for testing.