In the US, except in very limited circumstances, it's illegal to use or sell a signal jammer device intended to block communications. One Florida man is learning that the hard way.

The Federal Communications Commission on Wednesday slapped Jason Humphreys with a $48,000 fine for using a cell phone jamming device in his car during his daily commute to and from work in Tampa for up to two years. The jammer caused interference to cell service along Interstate 4, and disrupted police communications, prompting the FCC to investigate.

"This case highlights the danger posed to public safety by use of a single signal jamming device, which can disrupt all wireless and public safety communications in the area," Enforcement Bureau Chief Travis LeBlanc said in a statement. "These devices may not be used by the public under any circumstances."

After receiving an interference complaint from a local wireless provider, the FCC used a piece of equipment "designed to detect the source of the interference" to identify Humphreys as the culprit. Jammers, which are only legal in circumstances involving US Armed Services and the Department of Justice, work by transmitting radio signals that overpower, block, or interfere with communications.

"Jammers are designed to impede authorized communications, thereby interfering with the rights of the general public and legitimate spectrum users, the FCC said. "They may also disrupt critical emergency communications between first responders, such as public safety, law enforcement, emergency medical, and emergency response personnel."

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The FCC warned that jamming devices can "endanger life and property by preventing individuals from making 9-1-1 or other emergency calls or disrupting communications essential to aviation and marine safety."

This isn't the FCC's only recent jammer crackdown. Florida science teacher Dean Liptak recently found himself in hot water after blocking cell phone signals in his Fivay High School classroom.

Random Access: Google Gboard, new Xbox consoles Happy Thursday! Here's what we're discussing today: new Xbox One consoles, cellphone jammer, US still uses floppy disks for nukes, and Google Gboard. Posted by PCMag on Thursday, May 26, 2016

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