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The Pan-American television frequencies are different for terrestrial and cable television systems. Terrestrial 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 36 and occupies frequencies between 470 and 608 MHz.
150–156 MHz: "VHF business band", public safety, the unlicensed Multi-Use Radio Service (MURS), and other 2-way land mobile, FM 156–158 MHz VHF Marine Radio 156.8 MHz (Channel 16) is the maritime emergency and contact frequency.
Channel A was initially intended for use at Maghera but Channel B was used instead because of the risk of interference to (overspill) reception of BBC 405 line transmissions. [2] It was moved to Channel E due to interference from distant transmitters on channel 3 and channel A via certain atmospheric conditions and other reasons. Channel C was ...
The first 625-line system. Used on VHF only in most countries (combined with system K on UHF); VHF and UHF in China. E Early French VHF system (B&W only); very good (near HDTV) picture quality but uneconomical use of bandwidth. Sound carrier separation +11.15 MHz on odd numbered channels, -11.15 MHz on even numbered channels.
Since VHF and UHF frequencies are desirable for many uses in urban areas, in North America some parts of the former television broadcasting band have been reassigned to cellular phone and various land mobile communications systems. Even within the allocation still dedicated to television, TV-band devices use channels without local broadcasters.
A Illegal for public use [a] Public correspondence (ship-to-shore full-duplex) port operations Coast Guard, port operations Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (ship-to-shore full-duplex) 65: 156.275: 160.875
In 1945, TV channel 6 was assigned use of 82-88 MHz, [10] with the channel's audio located at a center frequency of 87.75 MHz. That same year the standard FM broadcasting band was reassigned to 80 channels from 88.1 to 105.9 MHz, which was soon expanded to 100 channels ending at 107.9 MHz (channels 201–300).
It is difficult to design a single antenna to receive such a wide wavelength range, and there is an octave gap from 216 to 470 MHz between the VHF and UHF frequencies. So traditionally, separate antennas (outdoor antennas with separate sets of elements on a single support boom) have been used to receive the VHF and UHF channels. [6]