The power to silence the annoying schmo yabbering away on their cellphone rests within a small black box the size of a cigarette pack. Selling for as little as $50, cellphone jammers can spew radio signals powerful enough to disrupt all nearby cell signals. The downside? It’s illegal.

The Federal Communication Commission says people who use cellphone jammers could be fined up to $11,000 for a first offense. Its enforcement bureau has prosecuted a handful of American companies for distributing the gadgets — and it also pursues their users.

Investigators from the F.C.C. and Verizon Wireless visited an upscale restaurant in Maryland over the last year, the restaurant owner said. The owner, who declined to be named, said he bought a powerful jammer for $1,000 because he was tired of his employees focusing on their phones rather than customers.

“I told them: put away your phones, put away your phones, put away your phones,” he said. They ignored him.

The owner said the F.C.C. investigator hung around for a week, using special equipment designed to detect jammers. But the owner had turned his off.

The Verizon investigator was similarly unsuccessful. “He went to everyone in town and gave them his number and said if they were having trouble, they should call him right away,” the owner said. He said he has since stopped using the jammer.

Of course, it would be harder to detect the use of smaller battery-operated jammers like those used by disgruntled commuters.

An F.C.C. spokesman, Clyde Ensslin, declined to comment on the issue or the case in Maryland.

$11,000 for a roving cellphone-free zone? Seems cheap to us.

Devices Enforce Silence of Cellphones, Illegally [NYT]

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