A Florida Resident Drove Around with a Cellphone Jammer for Two Years Before Being Caught

Alyssa Bereznak
National Correspondent, Technology
July 16, 2015

Many states have banned talking on your cellphone while driving, but Florida is not one of them. So 60-year-old vigilante Jason R. Humphreys took matters into his own hands.

As The Tampa Tribune reports, Humphreys brought a cellphone jammer along on his commute every day for two years. You know, to ensure that his fellow commuters remained focused on the road. Until two local sheriff’s deputies caught him in the act and slapped him with $48,000 worth of fines, which he must pay or otherwise respond to within a month.

It turns out that Humphreys would have gone undetected if it hadn’t been for a local carrier noticing that something was messing with its towers. MetroPCS (which is owned by T-Mobile) notified the Federal Communications Commission that there was a peculiar outage on a certain patch of the Interstate 4 highway and downtown Tampa exactly a year ago. The FCC looked into it and discovered that wideband emissions — broadcast activity with wide frequencies or wavelengths — were emanating from a blue Toyota Highlander.

Still, Humphreys kept on jamming for another year until two county sheriff deputies pulled him over. They were able to confirm his use of the cellphone jammer before they even searched his vehicle and found it behind a seat cover. As they approached his SUV, their two-way radios were disconnected from their dispatcher. 

How exactly can a cellphone jammer shut down service on an entire stretch of the highway? Your mobile phone works by connecting with the service network you pay for via cell towers. They’re scattered everywhere, so that your phone’s signal (or lack thereof) switches from tower to tower as you move about. 

Jammers interrupt service by transmitting a signal on the same frequency that it collides with your cell phone’s signal and the two cancel each other out. Most modern cellphones are engineered to automatically add power if they experience any sort of low-frequency interference. But when it comes to the strength of whatever was coming from Humphrey’s device, none of them stood a chance.

Image via HowStuffWorks.

Federal law prohibits importing, marketing, sale, possession or using these types of wireless signal jamming devices, in part because it’s unsafe for people who need to make 911 calls. These jammers can proactively block cellphones, Wi-Fi, GPS, aircraft communications and even two-way radios used by law enforcement and emergency personnel. 

Cell phone jammers were first developed for use by law enforcement and the military, so that police could block phone calls in a hostage situation or a raid. Now, however, they’ve made their way to the black market, aka Craigslist. 

The department later tested Humphrey’s device to discover that it could jam cell signals in three bands.

It’s unclear what brand or make of jammer Humphreys was using, but for some perspective, Antenna System & Supplies Inc.’s TRJ-89 jammer is able to block cell service within a 5 mile radius.

Humphreys is alleged to have said that he’d been using the jammer for 16 to 24 months on his commute. Meaning pretty much everyone around him was unable to use a cellphone. Even someone who had a dire emergency to call in.

Whether this made any difference in the quality of Humphrey’s commute, we are unsure. Unsurprisingly, he does not seem to be taking calls at the moment.

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