When I was a kid, I thought that there was no Channel 1 because all the TV stations would have fought to get that one. It wasn't until 1979 that I first saw a TV that had it.
I have never found out for sure if any stations ever actually transmitted on Channel 1 in the post-war period. There are lists of TV stations from about 1946 that do include several on Channel 1 around the USA.
At least one of the agile modulators I have seen (often used by us collectors to recreate NTSC signals for our collections) has the ability to operate on Channel 1. Now that I have a working TV with it (described
here), I am going to set up an in-house Channel 1 signal.