Tag Archives: ultrasonic

Teen mosquito repeller?

Turnabout is fair play

Interesting turn of technology against the adults!

An inventor in the UK developed a device to discourage teens from loitering outside shops by emitting pulses of a sound that teens can hear, but that most adults over the age of 20 cannot. Hmm, but then the teens turned it into a ringtone at a slightly lower frequency that they could hear in classrooms, but that most of the teachers (over the age of 30) cannot, and they’re using it for text messaging indicators in class.

You can hear an NPR interview with the inventor of the initial device and his teen daughter (who admits to having used it in class), at http://www.npr.org/templates/story/story.php?storyId=5434687

The link on the NPR website also has an MP3 of the sound. And of course, curiosity got the best of me, and I had to try to see if I could hear the sound. My well-past 30 year old ears cannot really detect it as a sound, but I felt a weird sensation while it was playing. Not really irritating, just odd. But maybe I’ll keep the file around … never know when it will come in handy.