Band III
Band IIIis the name of the range ofradio frequencieswithin thevery high frequency(VHF) part of theelectromagnetic spectrumfrom 174 to 240megahertz(MHz). It is primarily used forradioandtelevisionbroadcasting. It is also calledhigh-band VHF,in contrast to BandsIandII.
Broadcast Television
[edit]North America
[edit]The band is subdivided into seven channels for television broadcasting, each occupying 6 MHz.[1]
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
[edit]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 useSystem Bwith 7 MHz channel spacing 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 |
TheIrish(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 |
Oceania
[edit]Australiahas allocated 8 channels in Band III for digital television, each with 7 MHz bandwidth.
Channel | Frequency Range |
---|---|
6 | 174-181 MHz |
7 | 181-188 MHz |
8 | 188-195 MHz |
9 | 195-202 MHz |
9A | 202-209 MHz |
10 | 209-216 MHz |
11 | 216-223 MHz |
12 | 223-230 MHz |
Russian analog television is transmitted usingSystem Dwith 8 MHz channel bandwidth.
Channel | Frequency Range |
---|---|
6 | 174-182 MHz |
7 | 182-190 MHz |
8 | 190-198 MHz |
9 | 198-206 MHz |
10 | 206-214 MHz |
11 | 214-222 MHz |
12 | 222-230 MHz |
Radio
[edit]The band came into use for radio broadcasting at the turn of the 21st century and is used forDigital Audio Broadcasting.
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
[edit]Europe
[edit]In the UK and part of Ireland, Band III was originally used formonochrome405-linetelevision;however, this was discontinued by the mid-1980s. Other European countries (including Ireland) continued to use Band III for analogue625-linecolour television.
Digital television in theDVB-Tstandard 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 forDigital Audio Broadcastingis now being widely adopted. Sub-band 1 is used for MPT-1327 trunked PMR radio, remote wireless microphones and PMSE links.
North America
[edit]In North America, use of the band for television broadcasts is still widespread. Favorable propagation characteristics and reasonable power limits (up to 65kWforfull-powerdigital television,versus 20 kW or less onVHFBand I) has meant that many US broadcasters elected to move their full-powerATSCstations fromUHFfrequencies to Band IIIVHFwhen all full-powerNTSCanalog televisionservices in the US shut down in 2009.[2]
Amateur (Ham) Radio has a small allocation of the band, known as the 1.25meter band, from 219 to 220MHz and 222.0 to 225.0MHz for communications.[3]