Band III

 ( Broadcast Engineering ) 

Band III is the name of the range of radio frequency within the very high frequency (VHF) part of the electromagnetic spectrum from 174 to 240 megahertz (MHz). It is primarily used for radio and television broadcasting. It is also called high-band VHF, in contrast to Bands band I and band II.

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Broadcast Television

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North America The band is subdivided into seven channels for television broadcasting, each occupying 6 MHz. TV Frequency Table csgnetwork.com

174-180 MHz

180-186 MHz

186-192 MHz

192-198 MHz

198-204 MHz

204-210 MHz

210-216 MHz

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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:

174-181 MHz

181-188 MHz

188-195 MHz

195-202 MHz

202-209 MHz

209-216 MHz

216-223 MHz

223-230 MHz

The Irish (8 MHz) system is shown below.

174-182 MHz
182-190 MHz
190-198 MHz
198-206 MHz
206-214 MHz
	214-222 MHz
222-230 MHz

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

174-181 MHz

181-188 MHz

188-195 MHz

195-202 MHz

202-209 MHz

209-216 MHz

216-223 MHz

223-230 MHz

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Russia and other former members of OIRT Russian analog television is transmitted using System D with 8 MHz channel bandwidth.

174-182 MHz
182-190 MHz
190-198 MHz
198-206 MHz
206-214 MHz
	214-222 MHz
222-230 MHz

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Radio The band came into use for radio broadcasting at the turn of the 21st century and is used for DAB (Digital Audio Broadcasting).

It is subdivided into a number of frequency blocks used for multiplexes:

174.928 MHz

176.640 MHz

178.352 MHz

180.064 MHz

181.936 MHz

183.648 MHz

185.360 MHz

187.072 MHz

188.928 MHz

190.640 MHz

192.352 MHz

194.064 MHz

195.936 MHz

197.648 MHz

199.360 MHz

201.072 MHz

202.928 MHz

204.640 MHz

206.352 MHz

208.064 MHz

209.936 MHz

211.648 MHz

213.360 MHz

215.072 MHz

210.096 MHz

216.928 MHz

218.640 MHz

220.352 MHz

222.064 MHz

217.088 MHz

223.936 MHz

225.648 MHz

227.360 MHz

229.072 MHz

224.096 MHz

230.784 MHz

232.496 MHz

234.208 MHz

235.776 MHz

237.488 MHz

239.200 MHz

Grayed frequencies aren't used for DAB. Furthermore, some countries like Germany don't use channel 13's frequencies to prevent interference with aviation frequencies.

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Worldwide usage

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Europe In the UK and part of Ireland, Band III was originally used for monochrome 405-line television; however, this was discontinued by the mid-1980s. Other European countries (including Ireland) continued 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.

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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 kilowatt 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. FCC TV Query: US DTV construction permit listings for VHF Band I (ch 2-6) and III (ch 7-13)

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.

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