Channel 1 (North American TV)

For standards developed in the United States, television station allocations have commonly consisted of 6 MHz-wide spectrum groupings, known as "channels". The history of Channel 1 usage by North American over-the-air broadcasting stations, is divided into three main periods:

Prior to 1948 this was the first TV channel number, assigned to the lowest frequencies.

Due to interference concerns, Channel 1 was eliminated in 1948 from the NTSC analog assignments, meaning that TV set dials now started with channel 2. (Some cable television systems, which employed their own converters, included a channel 1, located at 72–78 MHz between channels 4 and 5, and moving channel 5 and 6 up by 2 MHz; however, this prevented channels 5 and 6 from being viewed on non-cable-ready television sets. Cable TV Channel 1 was also sometimes mapped to 99 (frequency range 114–120 MHz)).

With the switch from NTSC analog to ATSC digital TV standards, Channel 1 re-appeared to a limited extent as a "virtual channel" display, even though there was still no physical "RF" spectrum assignment for a "Channel 1"

Analog TV history

During the TV's experimental era, Channel 1 was relocated multiple times within the lower VHF spectrum. From 1937 to 1940, Channel 1 was allocated to 44–50 MHz, with visual and aural carrier frequencies fluctuating with changes in overall TV broadcast standards, prior to the establishment of permanent standards by the National Television Systems Committee (NTSC).

Effective July 1, 1941, the first commercial TV stations allocations were made by the Federal Communications Commission (FCC), based on NTSC recommendations, which consisted of 18 channels. The entire TV band was moved upward, due to the creation of the initial FM broadcast band, assigned to 42-50 MHz. TV channel 1 was moved to 50–56 MHz, affecting experimental stations in New York City, Chicago, and Los Angeles, with the visual carrier at 51.25 MHz and the aural carrier at 55.75 MHz.