Band III
Encyclopedia
Band III is the name of a radio frequency
range within the very high frequency
part of the electromagnetic spectrum
.
Band III ranges from 174 to 230 MHz, and it is primarily used for radio
and television
broadcasting. It is also called high-band VHF, in contrast to Bands I and II.
The Irish
(8 MHz) system is shown below.
. It is subdivided into a number of frequency blocks
405-line
television
. However this was discontinued by the mid 1980s. Some European countries (including Ireland) continue to use Band III for analogue 625-line
colour television. Digital television in the DVB-T
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
is now being widely adopted. Sub-band 1 is used for MPT-1327 trunked PMR radio, remote wireless microphones and PMSE links.
In North America, use of the band for color television broadcasts is still widespread. Favorable propagation characteristics and reasonable power limits (up to 65kW for full-power digital television
, 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
analog television
services in the US shut down in 2009.
Radio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...
range within the very high frequency
Very high frequency
Very high frequency is the radio frequency range from 30 MHz to 300 MHz. Frequencies immediately below VHF are denoted High frequency , and the next higher frequencies are known as Ultra high frequency...
part of the electromagnetic spectrum
Electromagnetic spectrum
The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....
.
Band III ranges from 174 to 230 MHz, and it is primarily used for radio
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
and television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
broadcasting. It is also called high-band VHF, in contrast to Bands I and II.
North America
The band is subdivided into seven channels for television broadcasting, each occupying 6 MHz.Channel | Frequency Range |
---|---|
7 | 174-180 MHz |
8 | 180-186 MHz |
9 | 186-192 MHz |
10 | 192-198 MHz |
11 | 198-204 MHz |
12 | 204-210 MHz |
13 | 210-216 MHz |
Europe
European Band III allocations vary from country to country, with channel widths of 7 or 8 MHz. The standard channel allocations for most of Europe are 7 MHz wide and are as follows:Channel | Frequency Range |
---|---|
E5 | 174-181 MHz |
E6 | 181-188 MHz |
E7 | 188-195 MHz |
E8 | 195-202 MHz |
E9 | 202-209 MHz |
E10 | 209-216 MHz |
E11 | 216-223 MHz |
E12 | 223-230 MHz |
The Irish
Republic of Ireland
Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...
(8 MHz) system is shown below.
Channel | Frequency Range |
---|---|
D | 174-182 MHz |
E | 182-190 MHz |
F | 190-198 MHz |
G | 198-206 MHz |
H | 206-214 MHz |
i | 214-222 MHz |
J | 222-230 MHz |
Radio
The band has only come into use for radio broadcasting within the last decade, and is used for Digital Audio BroadcastingDigital audio broadcasting
Digital Audio Broadcasting is a digital radio technology for broadcasting radio stations, used in several countries, particularly in Europe. As of 2006, approximately 1,000 stations worldwide broadcast in the DAB format....
. It is subdivided into a number of frequency blocks
Block | Centre Frequency |
---|---|
5A | 174.928 MHz |
5B | 176.640 MHz |
5C | 178.352 MHz |
5D | 180.064 MHz |
6A | 181.936 MHz |
6B | 183.648 MHz |
6C | 185.360 MHz |
6D | 187.072 MHz |
7A | 188.928 MHz |
7B | 190.640 MHz |
7C | 192.352 MHz |
7D | 194.064 MHz |
8A | 195.936 MHz |
8B | 197.648 MHz |
8C | 199.360 MHz |
8D | 201.072 MHz |
9A | 202.928 MHz |
9B | 204.640 MHz |
9C | 206.352 MHz |
9D | 208.064 MHz |
10A | 209.936 MHz |
10B | 211.648 MHz |
10C | 213.360 MHz |
10D | 215.072 MHz |
10N | 210.096 MHz |
11A | 216.928 MHz |
11B | 218.640 MHz |
11C | 220.352 MHz |
11D | 222.064 MHz |
11N | 217.088 MHz |
12A | 223.936 MHz |
12B | 225.648 MHz |
12C | 227.360 MHz |
12D | 229.072 MHz |
12N | 224.096 MHz |
13A | 230.784 MHz |
13B | 232.496 MHz |
13C | 234.208 MHz |
13D | 235.776 MHz |
13E | 237.488 MHz |
13F | 239.200 MHz |
Worldwide Usage
In the UK and part of Ireland, Band III was originally used for monochromeMonochrome
Monochrome describes paintings, drawings, design, or photographs in one color or shades of one color. A monochromatic object or image has colors in shades of limited colors or hues. Images using only shades of grey are called grayscale or black-and-white...
405-line
405-line
The 405-line monochrome analogue television broadcasting system was the first fully electronic television system to be used in regular broadcasting....
television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
. However this was discontinued by the mid 1980s. Some European countries (including Ireland) continue to use Band III for analogue 625-line
576i
576i is a standard-definition video mode used in PAL and SECAM countries. In digital applications it is usually referred to as "576i", in analogue contexts it is often quoted as "625 lines"...
colour television. Digital television in the DVB-T
DVB-T
DVB-T is an abbreviation for Digital Video Broadcasting — Terrestrial; it 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 the UK in 1998...
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 audio broadcasting
Digital Audio Broadcasting is a digital radio technology for broadcasting radio stations, used in several countries, particularly in Europe. As of 2006, approximately 1,000 stations worldwide broadcast in the DAB format....
is now being widely adopted. Sub-band 1 is used for MPT-1327 trunked PMR radio, remote wireless microphones and PMSE links.
In North America, use of the band for color television broadcasts is still widespread. Favorable propagation characteristics and reasonable power limits (up to 65kW for full-power digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...
, versus 20 kW or less on VHF Band I
Band I
Band I is the name of a radio frequency range within the very high frequency part of the electromagnetic spectrum.Band I ranges from 47 to 88 MHz, and it is primarily used for radio and television broadcasting....
) has meant that many US broadcasters elected to move their full-power ATSC
ATSC
ATSC standards are a set of standards developed by the Advanced Television Systems Committee for digital television transmission over terrestrial, cable, and satellite networks....
stations from UHF frequencies to Band III VHF when all full-power NTSC
NTSC
NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as...
analog television
Analog television
Analog television is the analog transmission that involves the broadcasting of encoded analog audio and analog video signal: one in which the message conveyed by the broadcast signal is a function of deliberate variations in the amplitude and/or frequency of the signal...
services in the US shut down in 2009.