A Brief Review: 68 Years of NTSC for CBS
CBS's first television broadcasts were experimental, often only for one hour a day, and reaching a limited area in and around New York City (over station W2XAB channel 2, later called WCBW and finally WCBS-TV).
The FCC began licensing commercial television stations on July 1, 1941; [on that day, they issued a license] to WCBW, (now WCBS).
On February 12, 1946, the newly completed AT&T inter-city coaxial cable was inaugurated with an experimental broadcast of Lincoln Memorial Services from Washington DC to NBC, CBS, and DuMonts stations in New York. This date is commonly referred to as the birth date of television network broadcasting.
The term "chain broadcasting" was used, as the stations were linked together in long chains along the east coast. But as the networks expanded westward, the interconnected stations formed great networks of connected affiliate stations. By 1951, the four networks stretched coast-to-coast, carried on the new microwave radio relay network of AT&T Long Lines.
In 1987, cross-country microwave radio relays were replaced by Fixed Service Satellites. Some terrestrial radio relays remained in service for regional connections.
In 2000, satellite capacity and quality were increased with the transition to digital modulation.
On June 19, the FCC decommissioned NTSC as the terrestrial broadcast standard leaving the ATSC digital terrestrial transmission. CBS Network followed by eliminating SD satellite distribution on June 24 2009, 68 years after NTSC was first licensed to CBS.
Courtesy Charles Kerman CBS Affiliate Systems