Device invented to scare off horrible youthsSonic punishmentBy Nick Farrell: Wednesday 30 November 2005, 06:41A WELSH boffin has worked out how to stop children and teens from misbehaving by walloping them with a high frequency buzz that cannot be heard by grown-ups.Howard Stapleton used the fact that children can hear sounds at higher frequencies than adults and has built a device that will scare off teenagers who hang around outside stores and cause trouble.Called the Mosquito, it can be heard by most people younger than 20 and almost no one older than 30.The sound irritates young people so much that they slope off and grow their acne elsewhere.Stapleton tested it at the Spar store which was a magnet for the teens of Barry in South Wales. Instead of joining nice choirs like good Welsh teenagers should, kids in Barry would intimidate customers, fight, or shoplift.A blast from Mosquito and it appears they become someone else's problem. According to the shop's owner, the teens were running around with their fingers in their ears begging him to turn it off.He told them it was to scare birds away because of a bird flu epidemic. You get a lot of bird flu in Barry.Teens can still shop in the store. It is just that they don't like to hang around much.