Alarm is used for ringtone
A yob-busting alarm using ultra high sound to drive teenage thugs from shopping centres has been hijacked to create inaudible classroom ringtones, it emerged today.

Techno-savvy school kids are getting away with using mobile phones in class through the creation of ringtones adults cannot hear.

British firm Compound Security has been praised by the police for its Mosquito device which was developed to stop teenage gangs hanging around outside shops.

Once installed on a building, it emits a high-pitched sound, like a constant insect buzzing, to drive the problem away.

It is highly effective because it cannot be heard by most people over the age of 20.

Howard Stapleton, Managing Director of Merthyr Tydfil-based Compound Security, said he was "amazed" by the children's creativity.

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Publication Express & Star (Walsall)
Date 24 May 2006
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