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| Radio Microphone Licensing
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| On this page we have produced a summary of what we understand to be the current situation with regard to the licensing of Radio Microphones within the UK.
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DISCLAIMER
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| The information presented on this page is our interpretation of the regulations published by the Joint Frequency Management Group and in no way should these be taken to be up-to-date or accurate. Those intending to use Radio Microphones should consult the JFMG website or contact the organisation directly to ensure compliance with the current regulations. Live Systems Ltd will accept no responsiblity in respect of individuals, companies or organisations making incorrect licensing decisions based on the information presented on this page.
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| Radio Microphone use is regulated in the UK by the Joint Frequency Management Group (JFMG). They are responsible for managing the part of the radio spectrum used by radio microphones. They regulate who can use what frequencies and where they can be used in order to prevent disruption to service for users of transmitting equipment. JFMG is, to all intents and purposes, a non-profit making body, who's fees are mainly to cover the administration of the licensing system.
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| Radio Microphones may be used in different parts of the frequency spectrum. Some frequencies are de-regulated and may be used without a license. Others require the user to obtain a license from JFMG and will depend on the type of use, duration and location.
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| We'll now explain some of the terminology associated with licensing. First off, let us take a look at the two different types of Radio Microphone - VHF and UHF.
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VHF Radio Microphones
| VHF (or Very High Frequency) based systems tend to be the older type of radio mic systems. They are usually based around a crystal and as such, have a fixed frequency. VHF, in terms of radio mics, refers to the range 173.800 Mhz to 217.000 MHz. Only certain fixed frequencies are available to be licensed. We will dicuss these later in this document.
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UHF Radio Microphones
| UHF (or Ultra High Frequency) based systems use a frequency synthesis technique which allows them to be configured for a range of frequencies and are therefore much more adaptable. UHF radio mics operate in the range 470.000 Mhz to 865.000 MHz. However, it is uncommon to find such systems using frequencies below 830.000 MHz.
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De-Regulated Bands
| A certain part of the frequency spectrum is set aside for operation without a license. We refer to these as De-Regulated Frequencies. Any device operating within this band can be used without any application to JFMG for a license providing the device conforms to the appropriate equipment specifications.
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| Naturally, it would seem like a good idea to run your radio microphones within this band as no license fees would be incurred. However, many other devices use this band: cordless phones, radio controlled toys, walkie-talkies, taxi companies - to name but a few. As you can imagine, there is a relatively high risk of interference from other sources on the de-regulated bands and this makes them a non-starter for serious radio microphone applications.
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Licensed Frequency Bands
| Where a licensed frequency is required, there are two main types of licenses which can be applied for - Shared frequency and Coordinated frequency.
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| Shared frequency bands are available for both VHF and UHF systems and comprise a block of frequencies which are available for use throughout the country. Users who obtain a license for these frequencies will normally purchase the license for a year and this allows them to use these frequencies anywhere in the country during this period without recourse to JFMG. As the name suggests, however, these same frequencies are shared by any other user holding a shared frequency license and so, although much better than using the de-regulated frequencies, there is still some risk of interference from other users.
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| Coordinated frequencies offer a solution to situations where interference is not a option. Coordinated frequency licenses are for a specific period of time (1-2 weeks) and at a fixed location. No other user is allowed to use those allocated frequencies around that location for the specified time period. This guarantees the user interference free operation. Care should be taken when selecting frequencies as not all frequencies are available at all locations. This is especially true with tourings shows and fixed-frequency VHF mic systems.
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Equipment Specifications
| In order to be used legally within the UK, radio microphones must conform to MPT 1350 (UK) or I-ETS 300 422 (ETSI). Equipment not conforming to these specifications is illegal for use within the UK. Additionally, there are limitations for output power. Handheld transmitters are limited to a maximum output power of 10mW. Bodypack transmitters, like those used with lapel microphones, can have outputs of up to 50mW to allow for absorbsion of the signal by the body.
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| If you would like any further information on this subject then either contact us or go to the JFMG website at
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| http://www.jfmg.co.uk
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Unit 6, North Leith Sands, Leith, Edinburgh, EH6 4ER, Scotland, UK Tel. 0131-555 5200
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