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Band I is a 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 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 ...
. The first time there was defined "for simplicity" in Annex 1 of "Final acts of the European Broadcasting Conference in the VHF and UHF bands - Stockholm, 1961". Band I ranges from 47 to 68
MHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...
for the European Broadcasting Area,
and from 54 to 88 MHz for the Americas
and it is primarily used for
television broadcasting
A television network or television broadcaster is a telecommunications network for distribution of television program content, where a central operation provides programming to many television stations or pay television providers. Until the mid- ...
in compliance with
ITU Radio Regulations
The ITU Radio Regulations (short: RR) is a basic document of the International Telecommunication Union (ITU) that regulates on law of nations scale radiocommunication services and the utilisation of radio frequencies. It is the supplementation t ...
(article 1.38). With the transition to digital TV, most Band I transmitters have already been switched off.
Television broadcasting usage
Channel spacings vary from country to country, with spacings of 6, 7 and 8
MHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...
being common.
In the UK, Band I was originally used by the
BBC #REDIRECT BBC #REDIRECT BBC
Here i going to introduce about the best teacher of my life b BALAJI sir. He is the precious gift that I got befor 2yrs . How has helped and thought all the concept and made my success in the 10th board exam. ...
...
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
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 wa ...
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 ...
;
likewise, the French former 455-line (1937-1939) then 441-line (1943-1956) transmitter on the
Eiffel Tower
The Eiffel Tower ( ; french: links=yes, tour Eiffel ) is a wrought-iron lattice tower on the Champ de Mars in Paris, France. It is named after the engineer Gustave Eiffel, whose company designed and built the tower.
Locally nicknamed "' ...
in
Paris
Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), ma ...
, and some stations of the French monochrome
819-line
819-line was an analog monochrome TV system developed and used in France as television broadcast resumed after World War II. Transmissions started in 1949 and were active up to 1985, although limited to France, Belgium and Luxembourg. It is associa ...
system used Band I. Both 405-line and 819-line systems were discontinued in the mid-1980s. Other European countries used Band I for
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 ...
analogue television, first in monochrome and later in colour.
This was being gradually phased out with the introduction of
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 ...
in the
DVB-T standard, which is not defined for VHF Band I, though some older receivers and some modulators do support it.
In the United States, use of this band is for analog
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 ...
(ended June 12, 2009) and digital
ATSC (current). Digital television has problems with impulse noise interference, particularly in this band.
Europe
In European countries that used
System B for television broadcasting, the band was subdivided into three channels, each being 7 MHz wide:
Italy also used a "outband" "channel C" (video : 82.25 MHz - audio : 87.75 MHz). It was used by the first transmitter brought in service by the
RAI
RAI – Radiotelevisione italiana (; commercially styled as Rai since 2000; known until 1954 as Radio Audizioni Italiane) is the national public broadcasting company of Italy, owned by the Ministry of Economy and Finance. RAI operates many ter ...
in
Torino
Turin ( , Piedmontese: ; it, Torino ) is a city and an important business and cultural centre in Northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. T ...
in the Fifties which was previously used in WW2 by the US to broadcast
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 ...
TV on channel A6 for military purposes, later donated to Italy, it had its video carrier shifted 1 MHz lower to accommodate the
System B standard. This channel was also widely used by private local stations until the switch over to
DVB-T.
Some countries used slightly different frequencies or don't use Band 1 at all for terrestrial broadcast television. The fast growing of digital television as well as the susceptibility of this band to interference during
E skip events in all European countries was accompanied by the progressive closedown of band I analog transmitters from 2006 to 2020.
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 ...
In the countries that use
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 ...
television broadcast system, the channel allocation in the VHF-I band is as follows:
Russia switched off Band I transmitters in early 2020. Ukraine, Moldova, Kazakhstan and a few other countries still broadcast analog TV on Band I in 2020.
North America
The band is subdivided into five channels for television broadcasting, each occupying 6 MHz (
System M). Channel 1 is not being used for broadcasting.
FM radio usage
The upper end of this band, 87.5 to 88 MHz, is the lower end of the
FM radio band. In the United States, the
FCC
The Federal Communications Commission (FCC) is an independent agency of the United States federal government that regulates communications by radio, television, wire, satellite, and cable across the United States. The FCC maintains jurisdictio ...
will occasionally issue a license for 87.9 MHz (though it only does so on rare occurrences and special circumstances;
KSFH
KSFH was an American non-commercial educational FM radio station licensed to operate on 87.9 MHz with an effective radiated power of 10 watts. KSFH started as the radio station of Saint Francis High School at Mountain View, California. It ...
was the most recent standalone station to use 87.9); 87.7, which is approximately the same frequency as the audio feed of channel 6, is used by some television licenses to broadcast primarily to radio, such as
Pulse 87
Pulse 87 is an online radio station with an Electronic dance music, EDM music format. It started out as the audio feed of a Channel 6 radio stations in the United States, channel-6 “Franken-FM” television station in New York City, audible on t ...
's stations.
In Japan and some former Soviet republics frequencies lower than 87 MHz are still used for the
FM broadcast band.
In Brazil, with the phasing out of the
PAL-M
PAL-M is the analogue TV system used in Brazil since 19 February 1972. At that time, Brazil was the first South American country to broadcast in colour. Colour TV broadcast began on 19 February 1972, when the TV networks Globo and Bandeirantes t ...
analog broadcasts,
AM radio
AM broadcasting is radio broadcasting using amplitude modulation (AM) transmissions. It was the first method developed for making audio radio transmissions, and is still used worldwide, primarily for medium wave (also known as "AM band") transmis ...
stations has being migrated to a new
FM radio band between the frequencies from former analog TV channels A5 and A6 (76.1Mhz to 87.5Mhz) called
Extended FM
Extension, extend or extended may refer to:
Mathematics
Logic or set theory
* Axiom of extensionality
* Extensible cardinal
* Extension (model theory)
* Extension (predicate logic), the set of tuples of values that satisfy the predicate
* Ext ...
or e-FM.
Amateur radio and TV DX
The
6-meter band (50 MHz) and the
4-meter band
The 4-metre (70 MHz) band is an amateur radio band within the lower part of the very high frequency (VHF) band.
As only a few countries within and outside of Europe have allocated the band for amateur radio access, the availability of dedica ...
(70 MHz) are used by
radio amateurs
An amateur radio operator is someone who uses equipment at an amateur radio station to engage in two-way communication, two-way personal communications with other amateur operators on Frequency, radio frequencies Amateur radio frequency allocatio ...
.
Short wave-like propagation is only possible under special circumstances, including frequent
E skip events in the summer season. This leads to strong signals in the 800–2,000 km range allowing the
reception of distant TV stations (TV DX). World wide connections are possible but remain a challenge on these frequencies.
See also
*
Television channel frequencies
The following tables show the frequencies assigned to broadcast television channels in various regions of the world, along with the ITU letter designator for the system used. The frequencies shown are for the analogue video and audio carriers. ...
References
{{Audio broadcasting
Broadcast engineering
Radio spectrum