Sonic Repelling Device

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A new sonic device has been implemented in Philadelphia to deter late-night loitering and vandalism by teens. The device emits a sonic sound wave at a frequency between 17.5-18.5 kilohertz and is mainly audible from ages 13 to 25. Although created to only be heard by this certain age range, there is many who are outside the age range who are able to hear it clearly.

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