North American television frequencies

North American television frequencies are different for over-the-air (also called terrestrial) and cable television systems. Over-the-air television channels are divided into two bands: the VHF band which comprises channels 2 through 13 and occupies frequencies between 54 and 216 MHz, and the UHF band, which comprises channels 14 through 83 and occupies frequencies between 470 and 890 MHz. These bands are different enough in frequency that they often require separate antennas to receive (although many antennas cover both VHF and UHF), and separate tuning controls on the television set. The VHF band is further divided into two frequency ranges: VHF low band (Band I) between 54 and 88 MHz, containing channels 2 through 6, and VHF high band (Band III) between 174 and 216 MHz, containing channels 7 through 13. The wide spacing between these frequency bands is responsible for the complicated design of rooftop TV antennas. The UHF band has higher noise and greater attenuation, so higher gain antennas are often required for UHF.

The VHF band plan was modified several times before 1948. The last of these changes was the deletion of channel 1, originally intended as a community channel. This allocation of the spectrum was given to two-way land-mobile radio.

UHF channels 70-83 in the United States were reallocated in 1983. As of 2016, channels 52-69 are not available for normal, high-power digital television broadcasting in the United States, but some channels are available for use as low-power or translator stations.

In March 2008, the FCC requested public comment on turning the bandwidth currently occupied by analog television channels 5 and 6 (76–88 MHz) over to extending the FM broadcast band when the digital television transition was to be completed in February 2009 (ultimately delayed to June 2009). This proposed allocation would effectively assign frequencies corresponding to the existing Japanese FM radio service (which begins at 76 MHz) for use as an extension to the existing North American FM broadcast band.

Wireless microphones and medical telemetry devices formerly shared some of the TV bands, but transmitted at a very low power. After the migration of digital television in 2009, the Federal Communications Commission (FCC) banned these from using the 700 MHz band in the U.S., effective June 12, 2010. The 700 MHz band is now used for public safety communications and wireless broadband providers.

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