Cellphone Jammers

slugcountry

A recent plan by Regal Theatres to arm consumers with a button to call in ushers if someone is on their cellphone during a film got me thinking: Why not just jam cellphone transmissions inside theatres? Is it legal? Or even feasable?

http://sciam.com/article.cfm?chanID=...2BED4E5CB98096

Danger

I didn't bother checking your link, because I suspect that it's the same article that I read a few months ago.
Certainly it's legal. Cell phones are more of a nuissance than second-hand smoke. As long as the damping field doesn't extend beyond the property of the user, there's nothing that anyone can do about it. (This assumes, of course, that said field doesn't cause any harm such as reprogramming pacemakers.)
Anyone who is awaiting such an important call that it must be answered without regard to others has no right being in a public place anyhow. He should be sitting at home waiting for the call. In the case of someone like an on-call doctor, a simple pager (on a non-damped frequency) has always been sufficient in the past. Otherwise, arrangements can be made in advance with the management to have a call routed to the office and an usher dispatched to fetch the guy.

berkeman

Oooo, dang. Good point about pagers. I started thinking along the lines of how would you not block 911 calls from inside the theater, but the argument could be made that if there were an emergency, it would be better to walk up the aisle to the lobby and use a land line anyway.

But the emergency pager issue -- that's harder. I don't know how the new pagers work.... I think the old ones in the US just piggy-backed on AM or FM broadcast band signals, but I'm not even sure about that. Anybody know? Maybe I'll google if I get some time this afternoon.

marcusl

Jamming might be legal in Danger's country of residence but it's expressly illegal in the US. Even on private property. Whether you can do it is a different question; the FCC has never prosecuted any violators. But only passive methods like screening your building with metal mesh are legal in the US.

berkeman

I dunno about that for jamming levels that are below the FCC unintentional radiator limits for the associated bands. But there is that clause about how you're not supposted to cause interference with valid commercial traffic, so I guess you're right.

Interesting point about the shielded buildings. I wonder if they have to post signs at entries so that people with life-critical pager services know that they will be off the air inside.....

Ivan Seeking

Not only have some theaters been experimenting with cell phone jammers, there was a recent story about text messaging jammers for teachers. Students are using text messaging to cheat during tests.

However,
http://www.newhousenews.com/archive/story1a092200.html

Averagesupernova

As a Ham I'm surprised you don't know this.

berkeman

Oh, it's worse than that. I've been working with RF more lately at work (I can't say why). Just haven't had a reason to look up pagers. Guess I better now, though, eh?

Moonbear

The thing with M.D.s on-call, though, is that they already have to carry cell-phones, and generally aren't issued pagers anymore anyway (they receive pages to their cell phones). No point carrying and paying for TWO services when the cell phones do everything (and they can call back right away and start giving instructions for care to be given to the patient until they arrive). However, they also know how to use their vibrate feature, and since the call isn't usually something that an entire theater should be listening in on anyway, they will step outside for the conversation. If they're on call, they aren't very likely to be heading to the theater anyway (that's almost a guarantee they'll get a call for an emergency, and not get to see the full movie), but if they do, you certainly don't want to be blocking them from getting their messages.

Talking on the cell phone in the theater is the same as talking to someone else in the theater, and can be handled the same way...hire ushers who do their job and ask people to be quiet or to leave if they continue talking during the movie.

JasonRox

How bad is the talking in theatres? I don't even see ushers around here. I've been to every theatre in my region (Niagara) as well as one outside. I've seen an usher only once, but I believe it was because some mother's son when in the wrong theatre and he was looking for him. I have never seen an usher in my hometown theatres.

Basically, you're all alone in the theatres with 100 people or something. Depends on the size and popularity of theatre and movie.

Moonbear

That's a big part of the problem, you never even see an usher anymore. When I was a kid, every theater had an usher standing near the door, or periodically walking up and down the aisle, during every movie. If someone started having a disruptive conversation, or causing some other trouble, the usher was there pretty quickly.

Danger

Ooops... I just rechecked. The morons at Industry Canada changed the law in 2002.
They should get jammed...

slugcountry

Now if only there was a way to jam little kids