Immediately after World War Two production of TV sets started in the
U.S. In 1946, only a few stations
were on the air, and broadcasting hours were very limited. By 1949,
almost all major cities had at least one station. At the end of 1946,
only 44,000 homes had a TV set; by 1949, there were 3 million TV
homes. By 1953, 50% of American homes had television.
In the late 40s, A T & T started building a microwave and coaxial
cable network to tie together TV stations in the U.S. By 1950, only a
small part of the country was interconnected, but by 1956, most
cities were linked to network programming.
There is a good selection of pictures of postwar American sets, along
with a lot of advertising material, at
Television History - the
First 75 Years.