Early microwave oven -Radarange, 1967The first commercial microwave oven, Raytheon’s Radarange,  was invented in the USA in the late 1940s. Domestic models began to sell in Japan in 1966 and in the US in 1967. The first imports to Australia were used mainly in take-away food outlets, but by 1980 around 150,000 households had a microwave, with penetration reaching 50 per cent by 1989 and around 77% by December 1995.