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Cell Phone Jammers: Coming To An Event Near You?
DarwinDan writes "The L.A. Daily News has an article about Cell phone jamming to prevent terrorists from detonating bombs remotely. Jamming technology is already being used "to protect President Bush." An interesting quote from the article: "Public safety is more important than public convenience.""
A wise man once said "Those who would give up essential liberty for temporary safety deserve neither liberty nor safety."...
;)
Of course, it's only arguable that cell phone usage is an "essential liberty", but then again you can argue just about anything on the Internet
Honey, I shrunk the Cygwin
Isn't THAT safety as well?
Besides, if someone wants to detonate a bomb they will find a way, and if they have to press the button themselves.
If you want to e-mail me, use my PGP Key.
"Oh my! That looks like a bomb! I'd better call 911...wait, why isn't my phone working?!"
...Followed by an explosion a few minutes later.
... aren't there laws (or doesn't the FCC have mandates enforceable by law) against this kind of deliberate interference with communications systems?
"It is dark. You are likely to be eaten by a grue." -- Zork
Change code from:
IF kaboomSignal THEN
blowup
ENDIF
To:
IF NOT dontKaboomSignal THEN
blowup
ENDIF
walkie talker freqs (49 mhz)
block fm radios?
block am radios?
block ham radio?
block light?
unless it's a faraday field in a box, part of the EM spectrum will get through... boom
to paraphrase lelo, bada boom..
every day http://en.wikipedia.org/wiki/Special:Random
So instead, they'll just detonate the bomb when there's an excessive amount interference.
I wonder if they jam pager frequencies as well? Pagers seem like they'd be a much more sensible choice. Much longer battery life, coverage is EVERYWHERE, and they don't broadcast a traceable signal.
I love how the goverment spends my money on useless crap instead of trying to make fewer enemies by not being so heavy-handed with the rest of the world.
I'll bet many of the survivors of Sept. 11 2001 made it through because of cell phone communications.
I doubt it. From what I remember, all the lines were clogged. It may have saved a few people but most of it was people trying to call relatives.
A high school near my home, which a friend of mine used to attend, used some kind of cell phone jammer because of the issues they were having with students answering phones during class time. It was rather annoying when I needed to use my cell phone on their campus at an after school function (awards ceremony).
What about the radio frequency that the president's body guards would be using to communicate with each other? I doubt they'd block that so there's a handy frequency to use right there.
An explosion at a Glasgow factory last week caused the building to collapse, and some of the people trapped inside managed to contact the emergency services by cell phone, making them easier to locate. There hasn't been any suggestion that terrorists caused the explosion, but if a jammer had been in place and had survived the explosion, more people may have died.
Decode these
No, that is a silly assumption. Detonators don't listen for simply a signal on a frequency. The need some kind of keyed code.... -PHiZ
Pretend I said something meaningful or insightful here.
Agreed. "Security theater" indeed. This is because there isn't much the government can do to stop terrorism. The "War on Terror" is fuzzier than the "War on Drugs", because terrorism is more dynamic a concept.
And yes, creating a radio controlled detonator is pretty easy.
If they're doing cellphone jamming, it'll actually make detonators more reliable on other frequencies. There won't be that RF burst when a call is taken and the mic on the phone is opened. Which means less premature explosions.
The previous has been a secret message to my comrades.
Of course, bomb makers could just put in a manual switch in series with the ringer detonation circuit to wait until the ring before activating that part of the mechanism. Unless there was some kind of random delay before the ring and/or a second ring at random. Add in unpreditability so safetly activating the detonation mechanism becomes unsafe.
Other things to do would be to make the ring circuit only work if the correct impedence was detected. You could get around that but then making bomb denotators would not be an off the shelf solution.
I read a while ago about this technique also being used to switch off mobile phones in places like theatres, cinema's and churches. So, it has yet another 'feature' for the public.
I don't want to be interrupted by a ringtone while watching Van Helsing, but I think switching my Nokia to 'silence' enables this far enough, I don't need help from others silencing my cellphone.
In need of reliable and affordable server monitoring?
The cell phones used in the Madrid bobmings were used for their timers. That's why they found one undetonated bomb, the clock read PM instead of AM. None of the bombs were detonated via recieving a call.
Are you...Are you some kind of genius?
No, ma'am, I'm just a regular Slashdot reader.
Eg in a theatre, the cell could act as a normal relay outside performance times, but suddenly become a black hole when the performance starts. (obviously it has to pretend still to be working, or the phones will just use another cell)
Such a system could allow emergency calls while blocking anything else.
_O_
.|< The named which can be named is not the true named
When catastrophes occur, there will be an info blackout around the affected area until the facts can be cleaned. Victims with (camera) phones must scare the hell out of our keepers.
As I've posted on a similar topic a while back, there are commercial devices available for usage in theatres / cinemas that although don't jam cellphones, do detect them. They basically play a loud noise (typically a really annoying voice saying "Please switch off your cellphone"), until they detect no more signals.