Thornbury FM was a local radio station in the United Kingdom, broadcasting to the South Gloucestershire

South Gloucestershire

South Gloucestershire is a unitary district in the ceremonial county of Gloucestershire, in South West England.-History:The district was created in 1996, when the county of Avon was abolished, by the merger of former area of the districts of Kingswood and Northavon...

 area of England. It operated from the market town of Thornbury

Thornbury, South Gloucestershire

Thornbury is a market town in South Gloucestershire, England, approximately 12 miles north of the city of Bristol, with a population of 12,342 at the 2001 UK census. The town hosts South Gloucestershire Council headquarters and is twinned with Bockenem in Germany. Thornbury is a Britain in Bloom...

 from November 2005 until November 2009 under the terms of Ofcom's Restricted Service Licence

Restricted Service Licence

A UK Restricted Service Licence , is typically granted to radio stations and television stations broadcasting within the UK to serve a local community or a special event...

 regime. This restricted the station to a maximum of two 28 day broadcasts per year in addition to its webcasts which operated 365 days per year, 24 hours a day.

About the station

Thornbury FM developed from an idea, suggested by local churches, to become the voice of the community of Thornbury in South Gloucestershire and its surrounding area. It broadcast on 87.7 MHz to the South Gloucestershire area from studios in Thornbury.

Thornbury FM adopted the Community Radio Charter for Europe, and included it in its constitution.

Thornbury FM has now ceased broadcasting, and has been replaced by GLOSS FM

GLOSS FM

GLOSS FM is a community radio station in the United Kingdom, which started broadcasting to the South Gloucestershire area on 19 April 2010.It is a member of the Community Radio Association....

 which began broadcasting on 19 April 2010. provides entertainment to a larger community than Thornbury FM although the studio, and most of the team, remains the same.

Programming

Thornbury FM provided programmes including news, sport, interviews, chat and music. These were produced by volunteers in Thornbury. It broadcast 24 hours a day.

FM transmission

Thornbury FM transmitted its signal on 87.7 MHz FM with a power of 25 watts ERP

Effective radiated power

In radio telecommunications, effective radiated power or equivalent radiated power is a standardized theoretical measurement of radio frequency energy using the SI unit watts, and is determined by subtracting system losses and adding system gains...

, which was the maximum permissible for RSL broadcasters in the UK. To help audibility within its coverage area compex audio processing was undertaken using a BW Broadcast DSP-X. This device reduces the dynamic range of the programme material which is a technique virtually all radio broadcasters use worldwide in order to deliver a loud, clear audio with no unintended distortion. The DSP-X also performed the function of stereo encoding. The transmission site was moved in the summer of 2009 from a low site in Thornbury town centre to a high site overlooking the Severn Vale. The resulting coverage area approximately doubled with this move, meaning that the station covered a potential audience of 135,000 people in South Gloucestershire from Bradley Stoke in the south, to Berkeley in the north, and from Yate in the east to Chepstow in Wales.

Studio

The studio was handbuilt by local volunteers to offer an extremely good acoustic environment through application of sound deadening materials on the walls and ceiling. Three AT4033 microphones are provided for the presenter and guests. These are connected to an Airmate mixer from D&R. The TBU

Telephone Balance Unit

A Telephone Balance Unit is a UK term for a device to convert the unbalanced audio signal carried on a copper phone line to balanced audio signal. It will also strip out any DC components...

 is also provided by D&R. Music may be played from Numark twin CD players, and also from software on the playout PC which is equipped with a professional M-Audio sound card. The main "live assist" audio software is delivered via a custom developed GUI

Graphical user interface

In computing, a graphical user interface is a type of user interface that allows users to interact with electronic devices with images rather than text commands. GUIs can be used in computers, hand-held devices such as MP3 players, portable media players or gaming devices, household appliances and...

on software called mAirlist. In the past a free player called Jazler Show was used, and a paid-for software called OTS-DJ which has since been replaced with another free station automation package called Zara Radio. The station used the latter for automated programming between the hours of 12 midnight and 7am, and extensively on webcasts in between RSL broadcasts. News on the hour was provided by IRN via a satellite receiver.

Studio to transmitter link

Thornbury FM used a high power licenced WiFi to link between its studio and its transmission site. Audio output from the studio was encoded into an IP stream using a Barix Instreamer device which offered extremely low latency compared to using a PC. At the far end a Barix Exstreamer device converted the IP stream back into audio.

Webstream

As well as FM broadcasts, Thornbury FM also broadcast its output 356 days a year, 24 hours a day on its webstream. Unfortunately the complexity of music royalty licencing means that between broadcasts webcasts were restricted to UK only, however the station was worldwide during broadcasts. The webstream was generated by Windows Media Encoder. Prior to encoding, the audio was processed using a free software audio processor called MBL4 which ensured a consistent audio level to prevent distortion. In order to route the audio signal within the PC from the soundcard input to this processor and then to the media encoder a software called Virtual Audio Cable was used which provides kind of virtual audio patch cables.

Webcam

Thornbury FM also had an in-studio webcam where listeners could check what the presenters were doing during the shows.

Suppliers

The studio equipment was originally supplied by Eastern Electronics. Studio and transmission facilities were maintained, upgraded and extended by Associated Broadcast Consultants

Licences

Thornbury FM was a legal radio station which paid for all licences. These included music royalty payments to Performing Rights Society, Phonographic Performance Ltd and Mechanical Copyright Protection Society. In addition, for each FM broadcast the station purchased a Broadcasting Act and a Wireless Telegraphy Act licence from the UK Government regulator Ofcom. News on the hour was played under licence from Independent Radio News.