If your cellphone kept dropping calls along Interstate 4 last summer, it could have been because of Jason R. Humphreys.
Federal authorities say Humphreys was operating a cellular jamming device during his daily commute between Seffner and Tampa. Humphreys, 60, told investigators he was using the jammer to keep people from talking on a cellphone while driving.
The Federal Communications Commission was not amused. The agency is proposing a fine of $48,000 against Humphreys.
Federal law prohibits the importing, marketing, sale, possession or use of such wireless signal jamming devices, in part because of the public safety issue of people needing to make 911 calls. Unlike radar detectors that are strictly passive, these jammers can proactively block cellphones, Wi-Fi, GPS, aircraft communications and even two-way radios used by law enforcement and emergency personnel.
Though illegal in almost every case, such jammers are gaining popularity, federal authorities said, and federal agents often pursue people looking to sell them on Craigslist.
The case along I-4 started on April 29, 2013, when the cellular company Metro PCS contacted the Federal Communications Commission because a transmission tower along I-4 would suffer in the morning and evening.
A week later, agents from the FCC's enforcement division in Tampa staked out the freeway on May 7, 8, and 9 and pinpointed a “strong wideband emission” in the cellphone wireless range “emanating from a blue Toyota Highlander sport utility vehicle,” with Florida license plates, according to a complaint issued by the FCC on Tuesday.
Another clue: When Hillsborough County Sheriffs deputies stopped the SUV, their own two-way radios were jammed.
The FCC's complaint says Humphreys admitted he owned the jamming gadget and said he had used it for the past 16 to 24 months “to keep people from talking on their cellphones while driving.”
Humphreys told investigators he thought the jammer would work in a 30-feet radius, said Larry McKinnon, a Hillsborough County Sheriff's Office spokesman. Instead, McKinnon said, the jammer was powerful enough it was affecting cellphone towers.
FCC officials seized the device from Humphreys after he was pulled over by sheriff's deputies. The next day, the problems with the cellphone towers stopped, Metro PCS officials said.
The use of the technology is illegal and dangerous, McKinnon said.
“You are cutting off any communication for any type of emergency,'' McKinnon said. “You are potentially putting people's lives at risk.”
The FCC action now starts a 30-day clock for Humphreys to either pay or give a reason why he won't. If he doesn't, the FCC can force payment.
Humphreys could not be reached for comment Tuesday, and no one answered the door Tuesday evening at his Seffner home.
The FCC has been focusing on such jammers for several years, partly as the devices are popping up more often on alternate markets such as Craigslist. Tuesday, a seller in Los Angeles listed one for sale for $300. “Rare Cell Phone Jammers,” the ad reads, “daughter won't stop using her cell or people are making phone calls in church — set up a jammer!”
Not every dropped call is due to a cellphone jammer, the FCC says. Rather it's often due simply to poor signals. But people who suspect jammers are foiling their calls can contact the FCC hotline at 1-855-55-NOJAM (1-855-556-6526).
Reporter José Patiño Girona contributed to this report.