The gateway to Washington's Chinatown is called th
The gateway to Washington's Chinatown is called the Friendship Arch. But the neighborhood isn't so friendly to teenage loiterers these days.

On the Internet, you can find devices that purport to humanely silence dogs that bark all the time. They include an app for your hand-held phone and something that looks like a birdhouse that emits ultrasonic sounds.

Noisy humans can be annoying, too, and public agencies and business owners are resorting to some of the same techniques to - if not shut them up - drive them crazy enough that they'll go elsewhere.

Teenagers got a dose of this treatment from storekeepers in Washington, D.C.'s Chinatown district, which has become a hang-out spot for loud, idle teens.

Fed up with their rowdiness and occasional fights, and the negative effect on potential customers, shop owners hung a gadget called The Mosquito outside the Chinatown subway exit.

Looks like a birdhouse. But the yappy neighborhood
Looks like a birdhouse. But the yappy neighborhood dog is eying it suspiciously.

The Mosquito, which its makers openly describe as a kid-deterrent device that moves along gatherings of anti-social youths, emits a loud, piercing beep at 17.5 kilohertz. This, the company maintains, is at the high end of the audible range that only teens and very young adults can hear. It drives kids crazy, according to a Missouri company that sells the device to playground owners.

When a Washington Post reporter went over to Chinatown to check out the device's effect, she ran into two visitors from Connecticut - one 19 and the other 20 - who were leaving the area to escape the high-pitched beep-beep-beeps.

This photo was taken in Murcia, Spain, not Washing
This photo was taken in Murcia, Spain, not Washington. But it depicts the kind of idlers that make local merchants nervous around the world.

But some older passersby also reported hearing the irritating sounds. And one young man complained that the constant beeping was, in his words, discrimination against young, black teenagers, who make up much of the Chinatown crowd. It's kinda mean, ain't it? he told the Post.

There was no report on the device's effect on nearby dogs.


Updating this story: On October 6, 2010, responding to a complaints that bombarding young people with annoying sounds amounted to age discrimination, the company that installed the Mosquito device in Chinatown removed it and announced it had no plans to put it up again.