Counter-top Microwave Oven
Invented by Percy Spencer, 1946, Waltham, Mass.
Developer Raytheon’s Amana division, 1967
Sold as “Radarange” for $495.
Counter-top Microwave Oven
Invented by Percy Spencer, 1946, Waltham, Mass.
Developer Raytheon’s Amana division, 1967
Sold as “Radarange” for $495.
Like many inventions, the microwave oven was discovered partly by accident, a by-product of postwar research into radar technology. In fact, a pocket full of melted chocolate gave Dr. Percy Spencer, a self-taught engineer for Raytheon, the clue he needed to further investigate the heating properties of a magnetron, a vacuum tube he was working on during his research into radar.
Spencer, who lacked even a high school diploma, decided to try a second experiment after he found his candy bar had become liquefied due to its proximity to the magnetron. He put some corn kernels next to the magnetron and soon they began merrily popping. He next put an egg down and the magnetron blew the egg into smithereens, spewing hot yolk all over the face of another researcher, a fellow who peered too closely at the precisely wrong instant.
Once the Aha! moment passed, the real work began: how could this invention be turned into a viable commercial product? The first fruit of such labor produced a 750 pound, 5’6” model installed in a restaurant in 1947. The model sold for about $5,000, or about $70,500 today. Though this early “Radarange” did, in fact, heat food quickly, its magnetron was water-cooled so the device was a water hog as well as an energy pig, thus very expensive to operate.
Raytheon microwave oven on the NS Savannah, Baltimore, Maryland, USA. Photo by Acroterion, 19 May 2012 under Creative Commons Attribution-Share Alike 2.0 Unported license.
The rapid drying properties of the device did attract the attention of industry. These early monster microwaves soon found themselves in factories, drying many products much quicker than previous methods.
Though redesigns and an air-cooling system for the magnetron soon reduced the price to below $3,000, that cost was far beyond middle class households. In the mid-‘50s Tappan, who licensed the technology from Raytheon, began trying hard to sell a home version but that model, priced at $1,295, was still too expensive for most households.
Raytheon’s Amana division finally cracked the consumer egg open in 1967 with the first countertop versions, priced at $495. By 1975, falling prices and lessening fears over the effects of microwave radiation, enabled sales to surpass gas ovens. By 1976, 60% of U.S. homes had a microwave, more, ‘tis said than had dishwashers!
Today microwaves are found in almost all kitchens and models can be bought for as little as $50. Annual global sales reach into the multi-millions and no candy bars are harmed: the microwave radiation is completely contained inside.
And here’s the scoop on the radiation for all the science nerds.
Electromagnetic Spectrum. National Institute of Standards Technology.