The microwave technology was first realised during WWII when the British developed high definition radar that used very high frequency signals. It was noticed that some antenna techs were being burned if they were close to the antenna during transmissions. It was the magnetron tube that made this possible, the same device is used today in the microwave oven. You see the old 'uns knew a danm site more than you give 'em credit for. I brought my first microwave oven, a Moffat, in the UK in about 1976.

My parents bought their first microwave in 1977. It was a Sharp Convection Microwave and it was 1500 dollars.

Mom used that thing for over 20 years.

Cost?

I think microwave ovens were in common use long before the late 1980s.

http://www.smecc.org/microwave_oven.htm

By 1975, sales of microwave ovens would, for the first time, exceed that of gas ranges. The following year, a reported 17% of all homes in Japan were doing their cooking by microwaves, compared with 4% of the homes in the United States the same year. Before long, though, microwave ovens were adorning the kitchens in over nine million homes, or about 14%, of all the homes in the United States. In 1976, the microwave oven became a more commonly owned kitchen appliance than the dishwasher, reaching nearly 60%, or about 52 million U.S. households. America's cooking habits were being drastically changed by the time and energy-saving convenience of the microwave oven. Once considered a luxury, the microwave oven had developed into a practical necessity for a fast-paced world.

We just bought them because we were told to by the appliance cartels. We didn't really understand what they were for, so they just sat around and got dusty for 30 years. Do you think we old fogies understood technology any better then than now?

Thumb this you whipper-snappers.