How well do cell phone signal jammers work?
 

I'm thinking of getting one of these to keep in the car, on the bike and bring into restaurants.

http://cgi.ebay.com/Personal-Cell-Phone-Signal-Jammer-Blocker-Device_W0QQitemZ330201589888QQihZ014QQcategoryZ294 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

My wife says it could make people on the phone even more dangerous on the road, since they might try to redial or pull the phone away from their ear to look at the display. What do you guys think?

Technically illegal in the U.S. although there are supposedly a few foreign distributors who will sell them here.

I've heard they work okay but don't know first-hand.

Ok for you to fiddle with a jammer while your driving but not ok for someone to talk on the phone. What a hypocrite.

Come again? How is it fiddling with something to turn it on when I get in the car and off when I get out? I never talk on my cell phone while driving, except on very rare occasion with a bluetooth. At the very worst, I'd have to press a single button to turn it off if I came upon emergency vehicles, which I did come upon on the way home tonight. All the cars around me were plenty busy rubbernecking instead of watching where they were driving, so I doubt shutting off my jammer would have mattered.

I didn't say it was legal. But I doubt there are too many cars on the road or people in restaurants or movie theatres or on the subway who would be able to spot a jammer. Oh, it's illegal to use a cell phone while driving in DC, but it's completely ignored.

I see, so wherever you drive/bike/eat you feel you have the right to jam cellular reception? Except of course when you decide it's necessary to turn this illegal device off. Got it.

I think you need to listen to your wife.

The DC cell ban is actually on hand held phones. Its ok to use hands free devices. Using a jammer could actually get you into a lot of hot water if you got caught. The potential unintended consequences would not be be good. While I am sure it seems reasonable for you to disrupt some cellphone yacking idiot who is driving, it is perfectly possible that a passenger is using a phone for a legal and reasonable purpose. You might also consider the range of frequencies that you are going to jam. We have multiple diffrent ranges in use in the US compared to the unit you might buy. You might inadvertently jam fire rescue or police radios. If you don't know all of these things you shouldn't even think about doing this. It not as simple as turning on a little device and correcting someone's misbehavior.

Jammers are illegal. If you use it, they will catch you; have no doubt.

What if I need to dial 911?

she's Chinese. If he doesn't listen, bad things will happen to him. Eventually.

Not that I know anything about that...

Why? Are bad people with cell phones somehow ruining your life?

Ok, how about in my place of business? It would certainly be cheaper to crank up a stereo but I fear they would just talk louder. I find it incredibly rude/annoying to have joes yacking away in my shop. On days I'm feeling a bit rude myself I've been known to tell them to take it outside.
Jim

Are you kidding? They are worse than drunk drivers and come in exponentially larger numbers. Worse yet, it's legal around here, except in DC, where it's ignored. Yes, handsfree is legal, but I don't see it very often in DC. Every single day I see dangers on the road caused by cell phone chatters. I have almost been run off the road while on my bike by cell phone cagers several times.

A jammer with a 10-20 meter radius is not gonna prevent anyone from calling 911 or interefere with emergency responders. It might, however, get people to put the phone down and look at the road when I'm near them. Maybe they'd even notice the string of cars behind them in the left lane or passing them on the right.

I never go to the movies, but if I did, I'd bring a jammer in there too. I don't mind cell phones in restaurants around lunchtime, but they can certainly ruin a nice dinner and they regularly make rides home on the subway a hell. I actually got a knife pulled on me on a bus in NJ after first telling a guy to quiet down his cell phone conversation and then yelling it to him after he continued. The rest of the passengerds agreed with me and had my back. A jammer would have kept it all silent.

I would never use it in DC. I regularly pass within a few feet of Secret Service vehicles and lots of other LEO's and firefighters. Jammers are unnecessary in DC. I got held up by the Libyan foreign minister's motorcade on the way to work yesterday and got lit up by Secret Service Suburbans tonight on the way home, when they wanted around me as I sat at a red light. But on the hwys. in VA and MD, they would at least create a safe buffer around me.

Know someone that has one. It works.

But it's pointless as 99%-100% of those you jam will never guess or know why they can't get a signal.

Where I lived in NY the coverage was so bad that easily 60-70% of my calls dropped at least once during the conversation.

And I think your wife has a point. You would be creating a frustrated cell phone user and further distracting them.

How would you feel if you were the cause of an accident?

Then there is the old "two wrongs" thing.

You're risking up to an $11,000 fine and a year in jail for the first offense. IMO, you'd be a bigger jerk than the rude people using their cell phones improperly. And I agree, your wife is right.

Listen to your wife.

Just to be practical, I wonder if jamming a driver's call would actually make you safer on the bike, maybe all the "hello, can you hear me" and redialing would make her even more distracted and dangerous.

Jam the HELL out of 'em!