I was doing some research at the local library this evening after work, and stumbled across this clipping from an old newspaper, dated 4/1/1943.

The story was about a new type of oven that was being tested at the Chambers Shelbyville Indiana plant. They called it a "Microwave oven."

[img]http://img419.imageshack.us/img419/1892/firstmicrowave8ad.jpg[/img]

The heart of the device was a microwave source called a Klystron Tube. In 1943 these ran off 480 volts AC, were as big as a house, and had to be coupled in to the oven box using a thick metal hose called a waveguide.

It seems Chambers had modified one half of a 1942 Imperial to operate from a Klystron microwave source instead of gas. The two Chambers engineers responsible for the test are shown in this image, standing off at a safe distance, and wearing tinfoil underwear.

The test was a success, and many fine sample meals were cooked using microwaves, with the gas off.

Unfortunately Chambers never marketed the device. When the Klystron tube was finally successfully miniaturized in the late 1970's, the Chambers company was already long gone.