In the 1960s, Litton <http://en.wikipedia.org/wiki/Litton> bought
Studebaker's <http://en.wikipedia.org/wiki/Studebaker> Franklin
Manufacturing assets, which had been manufacturing magnetrons and
building and selling microwave ovens similar to the Radarange. Litton
then developed a new configuration of the microwave, the short, wide
shape that is now common. The magnetron feed was also unique. This
resulted in an oven that could survive a no-load condition indefinitely.
The new oven was shown at a trade show
<http://en.wikipedia.org/wiki/Trade_show> in Chicago
<http://en.wikipedia.org/wiki/Chicago>, and helped begin a rapid growth
of the market for home microwave ovens. Sales figures of 40,000 units
for the US industry in 1970 grew to one million by 1975. Market
penetration in Japan <http://en.wikipedia.org/wiki/Japan>, which had
learned to build less expensive units by re-engineering a cheaper
magnetron, was more rapid.