Band III is the name of the range of
radio frequencies
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper ...
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 VHF ...
(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 from ...
from 174 to 240
megahertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, me ...
(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 transmit ...
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 advertisin ...
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
Irish may refer to:
Common meanings
* Someone or something of, from, or related to:
** Ireland, an island situated off the north-western coast of continental Europe
***Éire, Irish language name for the isle
** Northern Ireland, a constituent unit ...
(8 MHz) system is shown below.
Oceania
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
has allocated 8 channels in Band III for digital television, each with 7 MHz bandwidth.
Russia and other former members of
OIRT
The International Radio and Television Organisation (official name in French: Organisation Internationale de Radiodiffusion et de Télévision or OIRT (before 1960 International Broadcasting Organization (IBO), official name in French: ''Organi ...
Russian analog television is transmitted using
System D
System D is a manner of responding to challenges that require one to have the ability to think quickly, to adapt, and to improvise when getting a job done. The term gained wider popularity in the United States after appearing in the 2006 publica ...
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 syst ...
.
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, monochrom ...
405-line 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 advertisin ...
; 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 Telecommuni ...
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 Febr ...
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
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 syst ...
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 advanc ...
, versus 20 kW or less on
VHF Band I) has meant that many US broadcasters elected to move their full-power
ATSC stations from
UHF frequencies to Band III
VHF 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, instantaneous phase and frequency, ...
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)
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References
{{Audio broadcasting
Broadcast engineering
Radio spectrum