Originally Posted by difuse
I cannot imagine the '39 World's fair had any impact on US television development. The whole "introduction" of TV there was just David Sarnoff theatrics. There was nothing new in TV introduced there.
DEVELOPMENT, no, 1939 had nothing to do with it. It was pretty much done by then. DEPLOYMENT, it had EVERYTHING to do with it in 1939. Americans had not seen television before the Worlds Fair, Sarnoff use it to introduce TV to the American market, even though the BBC had been keeping a television schedule for a number of years prior along with Germany and to a lessor extent France. And even in 1939, experimental would still be a good word to use for the state of US television since there was no broadcasting to the RCA TV pavilion at the Worlds Fair. It was all closed circuit. Interesting note, when Germany invaded France, they dumped the French system and replaced it with the German 441 line system.
The FCC authorized the television service, effective Sept 1, 1939. Before then, it had been an experimental service with only NBC, CBS and Dumont with any transmitters and those were in New York City and even after Sept 1, none really kept any regular broadcast schedule, but NBC did try until the start of the war, but it was only at night and not every night when they all shut down the transmitters to concentrate on the war effort. US TV's birthday is considered Sept 1, 1939 even though it never really took off until 1946.
In reality, TV didn't have time before World War 2. Even before Sept 1, 1939, it was pretty obvious war was on the horizon for the US. It wasn't an "if", but a "when". It was widely known Hitler would strike somewhere, just where, (Poland on that fateful Sept 1 day) and even then, domestic production was starting to gear towards wartime production, just waiting for a declaration to be issued to stop domestic production. And many thought it would be Germany that would declare war on the US, not a Japanese sneak attack. After war was declared on December 8, 1941, 99.5% of research and production of TV in the US stopped until 1946. During the war years, many advances in electronics moved the state of the art to the point that when TV service was resumed in 1946, the FCC was on its way of making the changes in transmission of the video and change to FM audio and frequency changes so when stations really stated to come on the air in 1947, it is what we are familiar with today. It is interesting to note in the historic files of the FCC, work within the agency continued on TV through the war anticipating the resumption of TV after the war.
And yes, a TV from 1939 WOULD receive a black and white NTSC video signal, proper decoding of a color compatible signal would be debatable (it would be fun to try it though, you got one?), it would not receive audio since the audio section would be AM, not FM. FM not coming until 1946 with Sarnoff unsuccessfully stopping Armstrong's FM to be used for TV audio but then getting the FCC to move FM from the 40 MHz band to its current 88-108 band. A lot of stuff going on at the FCC with TV and FM in an 18 month time frame after the war.