Band III is the name of the range of radio frequencies within the

very high frequency Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves ( radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VH ...

(VHF) part of the

electromagnetic spectrum The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging fro ...

from 174 to 240 megahertz (MHz). It is primarily used for

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a tr ...

and

television Television, sometimes shortened to TV, is a telecommunication medium for transmitting moving images and sound. The term can refer to a television set, or the medium of television transmission. Television is a mass medium for advertising, ...

broadcasting. It is also called high-band VHF, in contrast to Bands I and II.

Broadcast Television

North America

The band is subdivided into seven channels for television broadcasting, each occupying 6 MHz.

Europe

European Band III allocations vary from country to country, with channel widths of 7 or 8 MHz. The standard channel allocations for European countries that use System B with 7 MHz channel spacing are as follows: The Irish (8 MHz) system is shown below.

Oceania

Australia Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by ...

has allocated 8 channels in Band III for digital television, each with 7 MHz bandwidth.

Russia and other former members of OIRT

Russian analog television is transmitted using System D with 8 MHz channel bandwidth.

Radio

The band came into use for radio broadcasting at the turn of the 21st century and is used for

Digital Audio Broadcasting Digital radio is the use of digital technology to transmit or receive across the radio spectrum. Digital transmission by radio waves includes digital broadcasting, and especially digital audio radio services. Types In digital broadcasting ...

. It is subdivided into a number of frequency blocks:

Worldwide usage

Europe

In the UK and part of Ireland, Band III was originally used for

monochrome A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, monochr ...

405-line The 405-line monochrome analogue television broadcasting system was the first fully electronic television system to be used in regular broadcasting. The number of television lines influences the image resolution, or quality of the picture. It was ...

; however, this was discontinued by the mid-1980s. Other European countries (including Ireland) continued to use Band III for analogue

625-line 625-lines is a standard-definition television resolution used mainly in the context of analog systems. It was first demonstrated by Mark Iosifovich Krivosheev in 1948. Analog broadcast television standards The following International Telecommun ...

colour television. Digital television in the

DVB-T DVB-T, short for Digital Video Broadcasting – Terrestrial, is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in Singapore in Feb ...

standard can be used in conjunction with VHF Band III and is used as such in some places. The use of sub-band 2 and sub-band 3 band for

is now being widely adopted. Sub-band 1 is used for MPT-1327 trunked PMR radio, remote wireless microphones and PMSE links.

North America

In North America, use of the band for television broadcasts is still widespread. Favorable propagation characteristics and reasonable power limits (up to 65 kW for full-power

digital television Digital television (DTV) is the transmission of television signals using digital encoding, in contrast to the earlier analog television technology which used analog signals. At the time of its development it was considered an innovative adva ...

, versus 20 kW or less on

VHF Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VHF ...

Band I) has meant that many US broadcasters elected to move their full-power ATSC stations from

UHF Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (on ...

frequencies to Band III

when all full-power

NTSC The first American standard for analog television broadcast was developed by National Television System Committee (NTSC)National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplement ...

analog television Analog television is the original television technology that uses analog signals to transmit video and audio. In an analog television broadcast, the brightness, colors and sound are represented by amplitude, phase and frequency of an analog ...

services in the US shut down in 2009.FCC TV Query: US DTV construction permit listings for VHF Band I (ch 2-6) and III (ch 7-13)
/ref>

References

{{Audio broadcasting Broadcast engineering Radio spectrum