Slashdot Mirror
Another Reason to be Annoyed by Cell Phones
lotussuper7 writes: "This story at newscientist (free, no registration, unlike the NY Times) has some insight into the amount of RF you may be getting from all those cell phones people around you are using. Might be time to buy a cell phone jammer."
Jammer ? Are you nuts ?
i can feel my skin melting already.... oh well.....
Cilck on this: ShutYourPhoneUp.com, then choose "Email a mobile phone abuser"..
Would you really want someone jamming *your* important calls? I wouldn't, and turnabout is definitely fair play. Besides which, jamming someone's phone is a DoS. Most people get rather upset over that sort of thing...
If you don't like cell phones, then go find somewhere that doesn't have them.
What is your Slash Rating?
Reduce your exposure to RF emissions by carrying around a powerful RF transmitter! Sure, that'll do the trick.
I'd be more worried about the cumulative effect of loads of commuters repeating the mantra..
$ strings FTP.EXE | grep Copyright
@(#) Copyright (c) 1983 The Regents of the University of California.
??
The article is talking about microwave EMF, not RF, and a jammer wouldn't help, because no-one would know so they would all still be trying to use their devices anyway- hence microwave radiation in carriages...
graspee
that's why a microwave oven has a lot of shielding, just to protect those bags of polluted water (yes, humans)
the risk of celluar phones is never publicly investigated on a large scale 'cause that's not what nokia, siemens and motorola make money with.
they don't care about your health; they're only in to it for the profit.
just don't tell me it suprises you
have a nice day
BOFH_org
The article looks like it's just a simulation of what may happen (with some microwave propagation tool), it would be more interesting to perform a measurement (I'm sure that the railways can "lend" a wagon for one day to the experimentalists) and really see what's going on...
It could be much less serious (or much more....).
over here in The Netherlands, mobile phone jammers are illegal. I think this is not too strange, considering the millions payed for GSM frequencies, and the billions payed for UMTS frequencies. No one except the license holder of these frequencies may broadcast on them.
Some forms of transportation already have "designated smoking areas" .. next we'll have "designated cell-phone areas" as to not mutate the innocent people around them (similar to second-hand smoke).
On another note, I would love to see restaurants take a stand on phone usage within their walls. At least force people to turn off the ringers and use vibrate instead.
"Might be time to buy a cell phone jammer."
;-)
No thanks, my cell phone came with a free jammer...it's called AT&T wireless service
Sent from your iPad.
Might be time to buy a cell phone jammer."
So essentially, transmit even more microwaves to jam people transmitting microwaves!!!
To prevent the problem in the first place, there should be a regulation body disallowing use of cellpones in trains, much like airlines regulation. Or a mechanism to defeat cell phone usage by blocking the range of frequencies, preventing people to make calls.
I remember when they said cell phones gave you brain tumors! BULLSHIT! Now they say that a train full of cellphones exceeds the recommended electromagnetic fields one should experience. WELL WHY WOULD A COMPANY WANT ITS CUSTOMERS DEAD? I mean come on, they need you around to subscribe to thier service. Next thing you'll tell me is that smoking is bad for your health. BAH!
While everyone else is getting brain cancer, I've been wearing my Aluminum Foil Deflector Beanie for years.
Just a myriad of uses for these things...
Websurfing done right! StumbleUpon
Whats really needed is a giant electromagnetic pulse which would destroy the electronics in the phone. Wow! what a place it would be without all the rude assholes who constantly babble around, talking ridiculously loudly, acting important without merit, trying vainly to impress others. What they really need to realize is that no one cares what the hell their talking about.
"Tsuyoshi Hondou, a physicist from Tohoku University in Sendai, Japan, who is currently working at the Curie Institute in Paris, says Japanese commuter trains are often packed with people surfing the web on their mobile phones."
Ok, I am gonna ask a naive question here. I live in Hotlanta (or Atlanta, but if you have been here you know what I mean) and I have taken good ole MARTA enough. However, I have not seen anyone using a cellphone to surf the web. (Or maybe there is some new method of websurfing by putting it to your ear that I don't know about) I think this is because of two reasons....
1) have a fancy phone, you increase your chance of getting jacked, and MARTA ain't the safest rail system.
2) just not big in the southern US.
Anyone care to prove or disprove my thoughts? We all know cell phone advances occur at a much higher rate in EU, so is this a legitimate concern? Seems to me we got too many other things to worry about other than a stupid cell phone, but that's just my opinion.
Sent from your iPad.
a slightly more intelligent person, having the same hypothesis, just went in and measured the fucking thing, rather than coming up with some bullshit math and explanations of how it /MIGHT/ happen. Where the hell is the proof? I don't buy it, that this guy came up with such great mathmatical proof and NEVER EVEN FUCKING TESTED IT.
Some nerdy slashdotter want to head out and measure it themselves while this jackhole is sitting there with a pencil? Please post your results.
-- 'The' Lord and Master Bitman On High, Master Of All
Over here we lick the boots of our government and let them tell us how we have to run our airwaves. ......
oh, so do we...
why don't they just use RF absorbant paint on the insides of the train.. seeing as it's not the phones that do the dammage it's the REFLECTION of the RF waves thats is putting it over the limits...
Just Limin' Mon
What microwave actually does to you: Microwaves heat things up "inside-out", basically they heat the water molecues of the object. When the microwave is in contact with you (not good), all it really does is it heats up your tissues, and if your are exposed to microwaves long term, you would most likely get cancer. But cell phones haven't yet reached the point of really hurting you, but they might if there's a whole bunch, or when the technology gets more advanced. Same with cordless/wireless phones, (2 Ghz, 2.4Ghz, etc.), the Ghz resembles how strong the radiation is. The higher it is, the stronger. I once heard this news a couple years ago, this man who uses his cell phone a lot, and eventually he had a brain tumor that has a shape of a cell phone (creepy..)
http://www.palmzone.net
People are worried because of the word "microwave". A mobile phone cannot produce any great amount of RF heating, for a few simple reasons.
A microwave cooker uses a very high power magnetron (usually >500W), directed in a narrow, focused beam, into a resonant cavity (the oven itself) from a distance of around 6". Furthermore, the oven uses a specific frequency, much below which RF heating is much weaker, and you need a lot more power (somewhere around 2.45GHz).
Now, a mobile phone uses around 1 or 2 watts *peak*. In normal use, it won't go above 500mW rms, otherwise the batteries would last only a few minutes. Not only that, but the antenna is designed to spread the signal over a wide area.
Mobile phone cell towers are also pretty much safe - although they use a much higher power than phones (15W or so, IIRC) they tend to be stuck up on high poles, well away from people. Inverse Square Law, anyone?
Here in Scotland, we recently had a series of large protests about siting cell towers near schools. The protesters were mainly middle-class mothers, from supposedly posh parts of Glasgow. Damn near all of them had sunbed tans. I'd take my chances with a mobile phone cell tower before I'd risk skin cancer from a sunbed...
Yes, I'm on the train
Yes, I'm on the train
Yes, I'm on the train
and on and on and on....
I'm not an RF expert but I am a physicist. As far as I know radiation can damage your cells in two ways:
a) Direct heating
b) Ionization
The latter one is easy to dismiss by elementary physics. Unlike in the gamma radiation, the photons of the cellphone microwave radiation simply don't carry enough energy to damage the DNA strands. Hell, microwaves pack less punch per photon than the infrared (heat) radiation!
The heating argument is more difficult to deal with. In general, the power of the RF field is again far too weak to heat your brain significantly (=more than the temperature varies naturally). However, if several fields overlap in a certain way (a standing wave forms inside your skull), then I guess there might be a possibility for an interference "hotspot" to form. Again I think this is very unlikely. Even a small head movement or the movement of the radiation source will change the geometry and thus the interference inside your head.
Quite frankly I am surprised by the anti-cellphone mentality in this thread. Most of it seems to come from experiences with annoying cellphone users. However, that's not a problem with the cellphones. That's a cultural problem. People simply have not learnt the proper etiquette yet.
Where I live the cellphones have practically replaced the landline phones. If the adaptation of the cellphones continues at this rate, there will soon be a one cellphone per citizen -- and that includes the minors. When the use is this widespread, the people in general know how to switch their phones to silent mode for meetings, movies and concerts. Having your cellphone ring, for instance, in the middle of a movie is socially extremely bad behaviour. If you start talking on your phone in the theatre, you will get thrown out -- either by the theatre staff or by the rest of the audience.
The owls are not what they seem
Radiation found to be harmful, largest Radiation source found to be the Sun, blow up the Sun advises Slashdot.
Scientists claim radiation can be use to kill cancer, carry more mobile phones advises Slashdot.
Living in City can lead to lung disease, move to the country advises Slashdot.
Living in country results in lower salaries, move to City advises Slashdot.
Car pollution causes Global warming, buy bigger cars advises Slashdot.
Is there a risk from this RF, yup, is there more of a risk from people driving while using a mobile than from this... oh boy yes. Is there a risk from Coal fired powerstations from radiation... oh wow yes.
Passive Mobile phone usage, Caligormia to legislate.
An Eye for an Eye will make the whole world blind - Gandhi
that instead of doing all these calculations to determine what the amount of RF radiation might be that one might instead actually go on to one of these trains and take measurements?
In the presence of a jamming signal cell phones around you would increase their output power in an attempt to hear their basestation. So all you'll achieve will be a increased drain on their batteries - like, they'll last 3.5 days instead of 4. Not to mention the radiation you'll be getting from the jammer itself.
Resistance is futile.
Why does everybody still take this stuff seriously? Read the article- all this study does is establish that you get exposed to more RF radiation in a crowded train car than you do in other places. The scary part only comes in when it brings up these "international guidelines" which such exposure may exceed. Who established these guidelines, and how? The article does not say anything beyond the name of the organization, but I note that its name makes it sound like an independent, non-governmental organization- so this could be effectively anybody smart enough to give themselves a clever-sounding name
The idea that RF transmissions will kill you or cause cancer has a long and ugly history of bad science concealed by calculated emotional appeals. It was basically started by a guy whose wife (who used a cell phone a lot) died of brain cancer, from which he concluded that cell phones cause cancer. Most of the "science" that has been done on this issue is basically the same idiotic reasoning dressed up in white lab coats. It is highly likely that the organization setting this 'standard' is in fact one of the lobbying groups associated with the anti-cell-phone movement.
Consider- radio waves are extremely low-energy- far below the threshold necessary to break molecular bonds, which is how genuine cancer-causing radiation works. Thus, if RF waves do cause cancer, the mechanism by which they do this is A. different than for other sorts of radiation, and B. totally unknown.
Plus, as has been pointed out a million times, a 'jammer' is a device which drowns out a signal by emitting a much more powerful signal of its own, not by magically making the other signal go away. If RF waves give you cancer, the jammer will give you cancer faster.
"Never let your sense of morals prevent you from doing what is right" -Salvor Hardin
OK, so I'm getting lightly cooked by all the microwaves
flying around the train. What about the huge magnetic
fields caused by the motors and overhead lines?
And now the Swedes have found that fried potato
(chips, crisps etc) has worryingly high quantities
of acryamide!
Looking at the risk of dying in a car crash still
makes all these risks pale into insignificance.
Sounds like all the more reason to use a car instead! That way we can justify building more roads!
Sure there are dangers with microwaves, however as with all things, it comes down to dosage. Strong signals - bad. Weak signals - less bad OR no effect OR benificial. So what is it?
There is an awful lot of research into the effects of mobile phones (certainly here in Europe) as it is such a big issue and people are worried. However, so far no effects have been shown apart from usage of phones actually improving your short term memory by a small amount.
Still worried? Well here is a parallel example. Find yourself a large magnifying glass and stand underneath it in bright sunlight. You will be cooked. Does this mean that sunlight is dangerous? Well yes if its bright sunlight (sunburn / cancer etc). However at low levels it is good for you. Your body needs sunlight to produce vitamin D, without it you get rickets etc.
So will mobile phones kill you? The answer to that is a definite Yes. Many people have already died directly caused by mobile phones. How? Well by walking out in front of cars whilst talking, driving in walls whilst using them etc. Compared to this, this risk of getting cancer or other ill through mobile phone usage is tiny. Not nil, this can't be proved, but tiny.
wot no sig
We are talking about the words of a /. editor here. Not exactly the most thoughtful group.
NO JAM!
I hav ben using a sell fone 4 yearz nd it hasssnt effected me ate awl. me brain gets no damage frum my sell fone.
Oh well that was fun!
I'm a amateur radio operator and I can say that the field emissions from these phones is nothing to get worried about. These concerns reguarding RF exposure from celular phones are from people who are completely cluless. Most celular phones only have a ERP (effective radiated power) of only 300 milliwatts and only transmit when the user speaks thus saving battery power and only producing a duty cycle of 40% or so. The computer monitor you sit in front of radiates far more power, even the leakage around the door of you microwave oven is in the order of a few watts at 2.45GHz..
rm -r windows
"I bow to no man" - Riddick
Also, the 2.45GHz frequency is deliberately not the optimal frequency for absorption and heating of water, it's a tradeoff between heating and penetration (you don't just want to cook the surface of the food). I believe the optimal frequency is somewhere around 900MHz. Whatever it is, anything in the range from maybe 500MHz to maybe 3GHz is bad news: at some frequencies, it heats strongly but doesn't penetrate very deeply (risk of cararacts), at others, it heats less well but penetrates deeper (risk to your brain and organs).
The point of that article, too, is that many places where people use cell phones are cavities.
People used to think that radioactivity and X-rays were really nifty and harmless, but things turned out differently. Maybe we should learn from that and be more careful this time around.
So where does the author get 2 watts from?
And what about digital, which is what most phones use now. Don't they operate at even lower power?
kuy 555
Okay, okay, I understand the gist of what you are saying. What I'm puzzled by is how you threw in the initials "ESR" into one of your FUCKs. Was this a Freudian slip? Do you really mean to say that you want to fuck Eric S. Raymond in his tucchus?
Well, I suppose that a "noise cancellation" type of mechanism where an active out-of-phase "microwave" is generated to nullify the radiation could work.
And perhaps the shape of the carriage and the way that the the microwaves reflect off of its walls would create focal points in the train where the radiation is exceedingly high. Kind of gives "hot seat" a meaning.
i'm not scared of some little damn cell phone. It aint' nothing that some chain smoking and heavy drinking won't fix.
OK - so let's get geeky about this. Why do we need to broadcast continuously to disrupt mobile phones. Why not listen for outgoing packets and emit a nice big rf chirp when the base station tries to handshake.
Benefits -
prevents users dialling out
prevents users accepting calls
low rf power requirements
reasonable battery life
difficult for law enforcement to track down
Disadvantages -
illegal
more difficult to design
Any final year electronics students looking for an interesting project??
Keith.
The radiation is not strong enough to physically cook my brain or other internal organs. Evidence for the induction of cancer by this sort of radiation is not too strong I think. Anyone has a good link to a decent study about that? I believe most studies prove that we are not sure if there is such an effect.
The Bigger The Headache The Bigger the Pill
It's amazing how everyone is suddenly an expert on microwave radiation isn't it ?, and how we all know the results of exposure to raditation because we've seen documentaries about nuclear reactor accidents, and because, we've seen cartoons that show that all you have to do to turn into a big eyed green monster is get exposed to a little radiation.
l 1/ emspectrum.html
_ gc i775674,00.html
The media would have us believe that radiation is an evil thing that destroys and mutates anything it touches.
So let's just be a little more scientific here shall we, and find out a bit about what EM radiation really is.
Electro-magnetic radiation is a term referring to the radiated field (ie, moving energy) of all types of electro-magnetic waves, from completely benign low-energy stuff like the radio waves your tv and radio receive, to quite nasty stuff such as gamma radiation. The difference is the amount of energy (and hence frequency) involved, and what happens to matter when exposed to those energies.
A large portion of the EM spectrum contains radiation that is of such a low frequency that the most it could do is impart some heat (okay, maybe a lot of heat) into your body. Anyone who has ever stood outside in the sun (yeah I know, I'm talking to a bunch of IT geeks who have probably never gone outside), will have noticed that it feels quite warm. You may not realise you've just experienced what it's like to be exposed to infrared radiation.
Look around, and bask in the knowledge that without the radiation we call visible light hitting the back of your eyes, you wouldn't be able to see a damn thing out there.
Now go back inside, turn on your TV and enjoy the television signals that are propogating through your house and are being converted into a very weak electrical current by the aerial on your TV, which is then hugely amplified so that you can watch a cartoon about mutant ninja turtles who live in a sewer.
When you fall and break your leg, you get carried off to the local hospital, where they radiate your leg with a high-energy radiation commonly called x-rays. When they do this, they cover the parts of your body they don't want to radiate with layers of lead, since lead is a cheap and dense atom and tends to absorb most things that hit it. This provides a shielding affect, which is good, because x-rays *are* dangerous if you are exposed to them for too long.
The reason that x-rays and gamma rays are dangerous, and radio waves and visible light are not, is that high-energy radiation contains sufficient energy to break the bonds within an atom, and can knock off electrons - creating a charged atom (known as an ion).
To say that another (simpler) way, ionising (ionizing for americans) radition is a dangerous thing to play with, since the cells in your body are not designed to operate well when charged. This is not to say that they will 'mutate' and your skin will turn green. More likely is that those cells will die and if you continue to be exposed to the radiation source, your body will be unable to produce new cells fast enough to replace the dead ones. Organs will shut down and stop functioning, and eventually your body will die from specific failures that I don't need to get into here.
Non-ionising radiation does not contain sufficient energy to break nuclear bonds, and thus is pretty safe to be around (The world would be a boring place without visible light).
Having said that, it's not entirely accurate to say that all non-ionising radition is safe - because it can destroy cells by heating them past the point that they can operate at. Anyone who has stayed out on the beach too long will be well aware of the danger of ultraviolet light, which is a non-ionising form of radiation, and thus does not destroy cells at an atomic level, but simply heats them up and burns them.
Fortunately the human body is capable of dealing with this, and the deeper layers of your skin produce a dark compound that is quite good (but not perfect) at absorbing UV radiation. Most people have seen this happening, and call it a sun tan.
This is not *quite* the same as the infra-red radiation that comes from say an oven or heater - that too can burn your skin, but since it has a different level of energy, and thus frequency, the exact manner that damage occurs.
What may surprise many people is that MICROWAVE radiation (1ghz - 100ghz) is also non-ionising. The damage it can cause is thermal, just like UV, radio, tv, infra-red, and ultra-violet radiation.
Microwave ovens work at 2.4ghz by *heating* whatever it is that you put in it. The reason they are shielded is that the makers don't want to cook the people standing outside the oven. If you were stupid enough to stick your hand in a microwave oven and turn it on, your hand would suffer a similar fate to as if you had put it in a fire or over a bunsen burner.
Incidently, 802.11b wireless networking works at around 2.422ghz - the same freqency that your microwave oven works at, but at a much lower power level, which is why you won't even feel a warm spot on your hand if you stuck it in front of the aerial.
GSM cellphones operate at 980Mhz, 1800Mhz, and 1900Mhz, depending on what type of network you are on. Those frequencies are at the end of the 'radio' part of the EM spectrum and the beginning of the 'microwave' part. Bear in mind that the term 'microwave' is simply referring to the size of the wavelength, and covers frequencies in the range 1Ghz to about 100Ghz.
Don't just take my word for it - check for youself. Google knows all, but I'll give you a few starting points:
There's a nice clear diagram showing where the different energies (types of radiation) fit in to the EM spectrum on nasa's site:
http://imagine.gsfc.nasa.gov/docs/science/know_
And there's a good explanation of ionising and non-ionising radiation here:
http://whatis.techtarget.com/definition/0,,sid9
There may be reasons folks want to jam cell phones. Reducing RF almost certainly wouldn't be one of them. If you start interfering with it, the first thing it's going to do is turn the power up to try and talk over the interference. Congratulations: You have now made the cell phone transmit more RF, never mind the fact that your own jammer emits RF as well.
The point wasn't jamming calls for fun or to have a quiet area. The point was that having many people in a train car using their phones at the same time, can raise RF radiation to dangerous levels. Or so the researcher claims; personally I think his calculations a rather over-simplified. Further tests (i.e. additional research grants) are needed!
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
A Cell Phone Jammer! Great idea. Someone needs to invent one of those so i can buy it.
prohibiting the use of "devices that have an antenna" in trains same as in airplanes. I saw some japanese trains where the use of mobile phones was prohibited. Let's do some lobbying for it all over the world. It works against smoking so why not against radiating.
This sig is a true statement, but I cannot prove it.
Ever seen one of those wireless phones you have at home? So you can run around the house while speaking in it. Got any idea how strong that signal is? How often it transmits signals?
Or what about wireless ethernet for that matter...
We need science, and we need to know what is dangerous and what is not. But these reports, or the reports about the dangers of potato chips, is not especially valid yet. I belive that two independant studies has to be made before you can draw any conclusion, and both of them has to live up to certain scientific standards.
Don't want a jammer. But a way to snatch the phone number of the cute girl I'm sitting next would be much appreciated.
idiotic, that is. The idea that RF transmissions will kill you or cause cancer has a long and ugly history of bad science concealed by calculated emotional appeals. Yes and the history of tests proving the harmlessness of RF radiation is short and... oh, no, I mean nonexistent. People like you are the ones who go "Pollution from my car doesn't harm anything otherwise people would be dropping like flies." Usually it's better to prevent unknown damage than to say "We have no proof it's harmful because we haven't studied long term effects, so let's go ahead." This is especially true when it comes to things that harm not just the users but those people surrounding the users.
See Arthur C Clarke's "The Light of Other Days" in which one character refers to lawsuits that ruined PC manufacturers after users developed tumors from sitting next to XXGhz PCs in unshielded cases. (set in the not-too-distant future, of course.. SO- don't buy a plastic tower!!
...and he grinned, like a fox eating shit out of a wire brush.
this discussions here really reminds me on the discussions in the 50th years about X-radiation and how they would affect humans. (i still have to laugh when i see those TV spots and how "well" they informed the audience: and belive me, a couple billion dollars are as much as important as the cold war). why should the mass media should us inform in a proper way? After all they get the information from the industry which is gaining money with cell phones. And dont belive that politicians are worried about our health. why should a politician risk his head on a "truth" which could lead to dangerous health situations in 20 years (when he has the means - with his "small" pension - to cure/treat the syntoms of his sickness caused by exccessive use of cell phones). ...) near EMFs of 50 Hz.
Now i'm not a hypochonderiac, but analyzing how microwaves are affecting our health is not that simple as many here are think. a good example is the effect of electric power on humans. after 100 years of use of electric power some people suddenly react "strange" (headache, toothache, sleeplessness,
who knows what we will know in 50 years about EMF and health? i for my part try not to sleep near cell phones, switch it off when i'm not areas with good receiving, etc. maybe one day this precaution pays off. after all it is my health and i live only one time.
I take away your cell phone. Nobody likes to be on the recieving end, do they?
Please read up a little on how GSM works. If a cell phone cannot get a clear control signal from the base station (which is what jammers prevent phones from doing), it will not transmit at full power.
Cell phones don't shout out to base stations continuously. If you don't believe me, take your cell phone to a place where there is no coverage, and measure the emissions from it. You can put it next to an am radio for that, or use one of those key rings with an LED that flashes when your GSM phone is active.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Last year all of the train companies here in Tokyo were telling people they should turn their cell phones off on the trains because they might cause somebody's pacemaker to crash. I think Japanese have a problem with telling people "Will you shut that damn thing off - it annoys me" and instead come up with these more neutral excuses for telling people to turn things off. Judging by the success of last year's no cell phone campaigns, I don't think this one will be very successful either. Anyhow, web surfing (wading - try it using i-Mode) or writing e-mail puts out a lot less RF than talking since you're not continuously transmitting.
won't get me when I'm protected by the delorean's steel body. You should buy me one.
As someone who has been in a few large substations, and near to high power transmitters, they do have effect on your body. You feel dizzy and ill after being near to these sites - there are no two ways about this. Many others claim this as well.
Phones may not do this to such a great extent - but open up one of the many "monkey drum" microwave dishes found all over the place in the UK, and the USA as well I should imagine. What do you find? A conventional cooking microwave magnetron. Ok, slightly different, and usually of a lower power.
Radar can produce huge bursts of power - and round radar sites, there are exclusion zones to stop you receiving a dose large enough to make you infertile or even kill you. Precision Approach Radar can be very dangerous in this respect due to the fact that the frequency and power used are dangerous, the dishes are located at ground level, and some of them can rotate 360 degress in seconds (the unit has to realign when different runways are used, and if you are in the way). Yes, this is an extreme case... but it still shows something.
I think that dismissing RF as safe because it doesn't cause ionisation or heating is stupid. In the same way as smoking was once viewed as safe, and that skin cancer has only been noticed very recently. Often our bodies do not behave in the ways which we think they should. I just think we should wait to see all the evidence before we jump to conclusions.
Surely electric currents in the brain are affected by RF? Do we know if this is bad or not? People also die when they are using their phone and can't pay full attention to the situation they are in.
Other issues are that when many radio waves are in a small space, they do not always combine to produce the same frequencies. Harmonics and other frequencies are generated, so saying that the frequency that the phone transmits is not dangerous doesn't mean the area is. Powers can also mount up.....
And jammers tend not to be high power - they disrupt the signal in a more clever manner. Although in the short term, the phones will transmit with more power, people will turn them off or the phones will stop trying so regularly.
I don't have a mobile. I don't want one mainly for the reason I don't want to be conctacted when someone doesn't know where I am. Landlines tend to be cheaper as well.
Mmmm, my lunch wasnt cooked when i brought it in with me this morning....
dominionrd.blogspot.com - Restaurants on
Gadget gratia Geekus
Jouster
Back in the days when CB was popular people frequently ran "burners" that upped the power to 10s if not 100s of whats. Now if someone had one of them in their car, truck or house next to you
imagine the radiation you'd be absorbing then. Surely all truckers would have cancer by now?
Sure its a much lower frequency but I can tell you
from persojnal experience (I once held an aerial that was transmitting by mistake) that even SW
radio can heat you up quite considerably!
The problem is, there is no mention of any real-world measurements being taken. Maybe the model is fundamentally flawed. Maybe having people in the carriage causes the signals to be attenuated more quickly than the model allows for. Maybe the metal of the carriage is not a perfect reflector. Maybe there is destructive interference between phones like the fading on AM radio stations in the evening etc. After all, if too much of the radiation were bouncing around internally, not enough would get out to allow the phones to work at all.
I thought the idea was so you could see you keyring flash rather than have you phone ring at inapproipriate times.
Its much easy and you look less stupid glancing at a tiny keyring than holding you mobile phone, although nowadays most phones have a vibrate functions which seem s to me to be the best solution.
I have significant disbelief in this guy's theory. A signal from a phone radiates at 1/2 a watt less than 3 inches from your head, which is accepted by international telecommunications union (ITU) as an acceptable power level for safe use. At the respective frequencies that cell phones use, the power degrades by 1/2 (or 3dB) every few inches. If EVERYONE in a train car used their phone at the same time and at a precise location that created positive interference to one specific user, all the other users (assuming about 100 passengers) would have to use their phones about 10 feet away (considering multipath too). This guy is full of it or he must feel the need for more attention.
"Might be time to buy a cell phone jammer."
This reminds me a scene from Spaceballs, where Lone Star (Bill Pulman) fires a pot of raspberry jam at Dark Helmet's (Rick Moranis) radar.
"Raspberry. There's only one man who would dare give me the raspberry: Lone Star!"
If you covered someone's mobile in jam, that'd stop them using it. Only while they stopped to smash your face to a pulp, mind, but it'd stop them none the less.
In the basement labs here in my school nobody can receive any singal on cell phone. The phones (most of them) will then go to power save mode, emitting less RF.
-=-=-=-=-=-=-=-=-=-=-=-=-=- Max, the 4 eyes.
when one can use a cheap and long known device, a Faraday cage.
As for the train, the only area not covered is the windows, adding a fine mesh of wire (inside the glass) and connect it to the body off the train, and you have an effective mean of shutting down most of the mobile phone emmision, they only remaining is the mobile phones trying to reach a base station.
If people travel a certain amount of time, say 20 minutes or more, they are likely to turn off the mobile phone since there is no access until they get off the train. And they will save some power on the battery (not as big a problem as it used to be though).
Carbon based humanoid in training.
i.e. A 1 watt transmission at 1 Ghz will have as much of a heating effect as 1 watt at 2Ghz (assuming equal tissue absortion characteristics).
AFAIK, around the microwave range, higher frequencies have less of a heating effect on human tissue.
So which is it?
Banned from moderation 01-27-2002. Fuck you too
I've heard the the SNCF (the national railroad company) is evaluating people's response to such an offer (reserving one cellphone-less wagon for interested passengers on some trains).
As of today this is only a first test. If people happend to demand such service the SNCF will deploy the service on a larger scale.
No matter how you try to play whack-a-mole with facts as your hammer and nonsense-journos as moles, they always come up with something stupid like this.
It almost feels organized already - maybe they are trying to create a new business, motivated by peoples fear of something they can't see. Looking at examples, this marketing strategy has been really successful - look at all people who believe in some kind of gods, angels, demons - they are really easy people to suck money from or, for example, fly airplanes into buildings.
One question remains: is there someone behind this, trying to set up new business with this FUD, or is this just group behaviour of weasel journos?
at least in the u.s. (and probably other countries with regulated spectrum as well), jamming cell phones is illegal.
Poof.
How much RF will you soak up when you have a device in your pocket that will have to put out a 50-100 watt RF spike into every 1 khz of a 50-100 MHz wide frequency BAND? Your ass will melt. Besides: you're not soaking up that much RF from other people's mobiles, not compared to what they do, and if I were you I wouldn't worry so much about a few watts from a tower: if you want something RF to cry about, how about that 50+ kHz wide 50 MEGAWATT radio station that you live only a few miles away from, that's blasting you much harder than a tiny little cell phone tower. Sheesh!
I will agree with you, though, if you say a no-phone section ought to be created in resteraunts. You don't just drop your pants and crap on the floor at a restaurant, do you? No, you get up and excuse yourself and go to the bathroom. That's what people should do when the get or have to make a call in a busy social situ. Plus, all CP's should have a silent ringer.
Indeed, if you're in a restaurant, and someone starts gabbing and laughing on a cellphone right at his table, just go over to his table, pull down your pants, and take a shit right on his table, (preferably in his food, or his lap). When he says "hey!" Tell him, that that is what he is doing to your meal by yacking on his phone while you're trying to eat.
Just a suggestion anyway.
Finally, I ruled out driver or interrupt problems by demonstrating the same problems with a regular cell phone held nearby the computer. Apparently, the IBM laptop had insufficient shielding. All problems disappeared when I constructed a small aluminum shield which can be put on top of the external part of the card. This piece without material value still forms an essential part of my former boss's equipment, even after three years.
By the way: the distance needed (from an external cell phone) to disturb the computer was some 10 cm while the typical distance antenna-brain is clearly much smaller.
really, this was all over the press couple of years ago.. cell phone will kill yer and blabbablabba. the poster obviously doesn't have a phone(kudos for him for that).. around here _EVERYBODY_ has a cellphone. when they were starting to get _really_ popular the press was all over few reports that the phones will boil your head..
and it really isn't that much worse from staying in the sun.. geez, ppl use solarium too.
and i spend my days in front of computers with monitors that are much worse.. compared to phone which i use 10min/day.
world was created 5 seconds before this post as it is.
Many small amounts of toxins are also allowed in human water and food, however that doesn't mean the toxins don't eventually kill you or make you more susceptable to disease once you reach old age.
Spoon not. Fork, or fork not. There is no spoon.
they jumped the gun announcing the stuff about the stuff about the fried potatoes. the next day after more research it was found that the potatoes have to be signifigantly burned to have any cancer causing effects.
Not the RF stuff. That's worth looking into. But the culture of "I hate mobile phones" is not one that is reproduced around the world.
I live and work in Norway. A mobile phone here is an accessory, like a watch, that you carry with you and that has an important function. A lot of people here HAVE no other form of phone service, what with the cost of an installed land line to the house being roughly equal in price and far less convenient.
Norwegians, as I have seen, do not make their phones ring loud and then engage in conspicuous conversation so that everyone can see how important and/or rich they are. That's conspicuously-consuming American behavior, and it's no wonder you guys demonize the poor little mobile phone. If you stopped culturally programming your people to be motivated only by money and status symbols, you wouldn't have flashy jerks showing off.
A lot of low-end phones don't come with a vibrate mode, which is too bad. I personally think that's ALL that phones should come with. No rings or ringtones. You don't need a ringer at home... have you ever heard a phone on vibrate go off on your desk? The buzz is enough to wake the dead.
no one else has mentioned this. in the article the guy says that in his calculations he factored in that 30 people were using the phone in the one train car. not that the phone is on, but that 30 people are USING thier phones. here in sweden anyway i notice 1 or 2 people actually using thier phones while in the train car. not 30 people simultaneously.
Worry about the jail term. When you have to listen to one more idiot talk about how his wife doesn't shave her fat legs often enough, you're going to get irresistable urge to choke the living *daylights* out of him (brought on by RF exposure, no doubt), and then its off for a nice vacation in the local lock-up.
This is just theoretical. I'd really like to see some hard data on this. Has anyone taken time averaged measurements in crowded trains?
But if every extremely vocal teenybopper with a cellphone and unlimited minutes suddenly develops cancer and DIES.... I'm supposed to feel SAD about that... right?
It was nicer back in the day when it cost 30 cents per minute to use your cell, and thats if you were only making a local call. A lot of people had them, but nobody used them unless they HAD to, and even then they kept the conversations short and to the point. There was no fear of idle chitchat while in a movie theatre.
And no offense to women, but they're abusive phone users. This is nothing new. But before cheap cell phones, they were isolated to their own homes and didn't seem too compelled to share their hours long conversations with the rest of the world. But now, go into any large grocery store and I can almost certainly guarantee you that there will be at least ONE woman in there gossiping up a storm with someone over the cell, almost completely oblivious to the world around her. Its worse when they drive.
So hey, I'm all in favor. LET the phones cause cancer. Hell, make them even MORE dangerous. And the louder the user speaks, make it emit more radiation. Its the perfect way to rid the world of the people that seem to dedicate their lives to annoying others.
-Restil
Play with my webcams and lights here
Go to the office supplies, wrap a handful of lead pencils around your mobile, with 2 elastic bands, and you have your own mobile phone shield to protect you from harmful radiation, that doubles up when you need to take a message.
And be the envy of your office..
the jammers emit even more RF to interfere with the cellphones.
and it's always emitting. not wise.
Either A: They are wrong about the RF and there is no problem. Or B: The train does reflect RF, therfore cellular signal both transmitting and receiving are weak, therefore nobody actually uses the cell phone, therefore No Problem.
As far as I know bluetooth uses the 2.45 GHz band as well.. It is the same frequency used in microwave oven.
I wouldn't start thinking about the harm of cellphone as long as no body get cooked by bluetooth device.
heres how we deal with the problem in britain
http://www.phonebashing.com/
It just plain stupid, let's make an RF version of slient machine!
First, I don't see all these supposive people dropping dead from RF over-exposure via cell phones. Maybe it's just me, or maybe it's one giant conspiracy. Right. Second, I think the person who has the most to worry about is the user. We're not talking second hand smoke here. The power at range just isn't significant to harm a 3rd party. Third, your worried about cellphones when you probably drive through a myriad of high intensity EM fields everyday!? Take a florecent light and walk under some high-tension power lines one of these days. Or put one in a mirowave. I'm sure you'll find the effect enlightening. Funny how a cellphone doesn't produce either of these effects, but it just happens to be everybodies whipping-boy of the day. I love it.
And you actually want to jam cell phone calls? I hope those people get their asses sued off the day somebody tries to phone in a life threatening injury but can't. If you have the right to jam my phone, I must have the right to slash your tires to keep from annoying me. I can't wait until they make jamming triangulators so they can find you, beat your sorry butt down and break your little toy. heh.
Ironically, I'm betting your little jammer will produce more EM radiation than a cellphone. I used to work on EA-6b Prowlers in the navy and you're going to have a tough time jamming without generating an equal or greater amount of power than the source. That, and the greater the range, the more power it'll require. Have fun irradiating yourself, chumps.
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True I guess, but the phones on the fringe of the jammer may still be able to contact the base station, and so Tx power may increase as they see the interference from the jammer.
Oh course, if your phone is just in your pocket and not in call then it isn't transmitting much anyway.
-- Mike
I forgot... You're worried about cell phones over the CRT your working in front of right now!? Oh this is too good.... And how many of those are in the average office...?
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If you build a device that behaves like a BSE, but accepting all connections regardless of provider , then within that area, all handsets will tend to lock onto it. Once they have connection on the control channel, they will mostly shut up. No incoming calls, and just a little power expended to keep the control channel alive.
I think somebody in Israel made something like this for use in concert halls (and probably for blocking the PLA).
"Microwave oven's output is typically from 600 W upwards. Are you really comparing this to hundreds of milliwatts?"
Ok... lets do some math... cell phone's peak power is about 2 watts. Times that by 300 people in a train, all trying to connect to their cell tower at the same time, after the train goes through a tunnel. (When the signal is faint, a cell phone boosts to maximum power to try to connect.) Suddenly, you have a train filled with 600w of microwave radiation. The shape of the train is much like a resonance chamber. Instant microwave oven... As the microwaves build standing waves, people in select areas of the train will burst into flames, while others nearby won't feel a thing.
Freaky.
I hear people in Japan regularly faint from heat stroke on trains... I wonder if some of it is already attributable to cell phones??
I don't think that you can phase out RF for some reason, like you can sound, that might be some idea to try, cancel out the waves in total!.
Tibbon
Tibbon
tibbon.com
well... roads, and aquaducts, education, and a sewage system...
perhaps essential is not the word, but grunting is overrated.
...not to use those obnoxious devices. I have no cell phone, and no desire whatsoever to get one.
There is in fact very little you need to know to get a rough estimate. Basically the train car is a resonator with Leakage (windows) and absorption (people and stuff). You emit some amount of microwave enrgy into the car--and it does not matter how you emitt it. Once the phone emits it its just plain old Elactomagnetic radiation. If there were no absorption the average field level in side the car will be something like
(phone power)/(1-R)
where R is the ratio of metal to widow area.
if there is absortion (by you or the seat cushions), then its less. My guess is that R is around 0.9, making the field level 10x higher. On the otherhand that's an average. There will be higher and lower hot spots in the carriage, typically about twice that level is certain to exist at points.
Now what is more interesting is this The total microwave enrgy release in to the car is not increased by the resonator, just the field strength. However, because it is a resonator, your probability of absorbing all of the the energy does increace. In otherwords the amount of power you absorb is never more than the rating on the phone. But in typical usage outside of a train car you dont even get a fraction of that because even 6 feet away the field stength is too low for you to absorb much of the energy. (most of it went a different direction). Inside the train car it does not matter how far away your stand (assuming no absorbing media), and the fraction you absorb is much higher. Roughly speaking it will be the same (order of magnitude) as if you had your head pressed to the phone.
but what I have ignored here is role of absorbtion. Each of those transmitters also comes with a human being to help share the absorption with you. plus most non-manmade materials have a modest microwave absortion if they are a centimeter or so thick. One can roughly approximate the situation like this: because of the resonator nearly all the microwave enrgy is absorbed inside the car. the fraction received by any one person is approximately the ration of the mass of the human divided by the total mass of all the other humans plus the total mass of all the absorbing materials.
so if you are in a car with 30 people, all using their cell phones, you probably are receiving a major fraction of one cell phones worth of power.
Of course some people think its not the power of the cell phone that does the damage but the field strength, and that is indeed higher.
It's one nice thing for the trains to not have to use cabin lamps within the next few years because by then all those hardcore cellphone users will have a nice radioactive glow emmitting from their heads.
$cat
Adobe only allows you to use their bricks IF you avoid products from Elcomsoft and Dmitri Skylyarov. . . (evil grin)
Lawyers have been trying for an "in" to sue telecomm companies for years. Most of the studies exploring links between cellphones and tissue damage are directly or indirectly funded by lawyer lobbies. So far, dozens of studies have produced no causal link. But they will continue trying, and articles like this will keep coming.
They won't sue TV manufacturers or Microwave manufacturers because the average jury member would rather have his head cut off than give up eating TV dinners while watching "Friends". But cell phones... ah, that is a different kettle of fish altogether. Many interests coincide to want their demise. Suburban homeowners nervous that a cell-tower in the vicinity could reduce property values for a start.
Magnus.
at rap (or hiphop these days) stars (and Mr. T) that wore 10-15mile worth of gold chains around their neck didn't you? they were smarter after all. you still don't get it? gaussian cage around their head. who's laughing now ;) run forest run ... to the nearest jewellry store. or just dig into wife's dresser.
No Loitering
No Solicititing
No Skateboarding
No Rolerblading
No Smoking
No Cell Phones
No Wireless Devices
Who keeps their keyring in view more often than their phone? It guess it's an "outside NYC" thing -- I just wouldn't understand.
From reading a lot of the comments here I think a lot of people should research what a jammer is and how it works.
ie: A jammer increases RF exposure not decrease it.
are we sitting in front/back of whilst we write about this?
. . . sorry, but the jammers emit just as much EMF as the phones, if not more so -- that's how they work!
I can't think of any reason why a call to measure actual, real world effects (when possible) should be called silly. The point is to determine whether any real harm is being done. Determining if it is plausible is informative but means little if it isn't actually happening and actually never happens.
Just go onto trains with the proper equipment (if he's so adept in this field, he'd have access to it, right?) and MEASURE the amounts? I'm suspicious of any research that's so purely existent on the back of an envelope, especially when the researcher has eschewed an easy opportunity to test the real world.
For your security, this post has been encrypted with ROT-13, twice.
How does the microwave oven heat food? It just so happens, by design, that water molecules resonate at the frequency (2.45GHz) that the ovens produce. Try nuking an ice cube sometime. It goes pretty slow until enough water melts, and begins to resonate... Since water makes up most of our food, this is a good system.
The catch is, what else resonates at around 2.45GHz? Well, DNA for one thing. And you don't really need to be cooked to a temperature of 160+ degrees for Cancer to kick in...
As for being only a meager 1-2 watts? I played with a meager 2 watt water-cooled laser once. It was too bright to look at, even with filters. I learned not to focus it on cardboard -- At a meager 2 watts, it kept burning holes through the cardboard.
Besides which, we are not talking about a 30 second exposure like all those cellular folks figured on. We are talking N watts for M hours a day, 7 days a week, 52 weeks a year. The genetic damage will accumulate.
From what I have read on newscientist in the past (mostly links from /. stories), they tend to be very short on real science and very long on politics and fear mongering. If they were really strong on science, I think they would have been a little more sceptical about the assumption that all of the radiation from the phones on the train would add, "much like light from different lamps would increase the overall illumination in a room."
The radiation is just as likely to subtract, which would mean that the more cell phones on around you, the better off you would be!
"I'm upset by all the RF radiation created by cellphone use around me. So, I'll go buy a device that emits lots of RF radiation in the form of noise to prevent anyone else from creating useful RF radiation around me."
That's what I'm getting from this, am I wrong?
Yes jamming is bad. But there are too many stupid people abusing their phones.
Cell phones have two tranceivers: one in the pager bands (around 220 mhz I think) and another in what is commonly called the 'cell bands' (800,900, mhz 2.4 ghz).
To jam one does not need to put out more power per se, just disrupt the link between phone and network. This could be done by jamming the pager band that the phone uses to set up the call and to know what 'cell' freq. pairs to shift to as you drive down the road (like the control chan. in ftp). This is where cell crackers grab their data from in order to clone phones.
I have been told a spark gap generator makes broad emissions across several bands and could do the trick here.
Any EE or cell engineers care to chime in?
Thanks for any info!
Not to mention that jammers should be illegal. A cell phone isn't much different from a ham radio, and you don't have the authority to jam that...
Cant smoke in public, but cell phones are okay. Is there realy a difference?
Enough of RF and microwaves crap! Let's talk about the REAL danger caused by cell phones: SUV and minivan driving Soccer-moms, and such. They drive along, not a care in the world (other than talking and driving and NOT paying attention to their driving) with their head cocked sideways to hold their cellphone with their shoulder. I cannot count the number of times I have almost been shoved off the road, or had to quickly switch lanes to avoid one of these cretins merging (without signal or looking for clear lane). Word of advice: USE A HANDS-FREE! Don't make our glorious Government feel they must enact a law enforcing their use to make us safe.
Plausible? What kind of controls are you thinking about? Reality check: the wavelength is 33 cm or less and the volume of the rail car is what? An overtone resonance like that would be very difficult to accurately simulate, particularly with all those bodies, fabric, plastic, windows and people moving around. Put one extra suitcase in there and everything changes.
There is no way to model a consistent RF behavior with a train car and a 33 cm long wavelength. All you have to do change one cell and the whole prediction falls flat on its face.
Nearly fifty percent of all graduates come from the bottom half of the class!
Of course, if you stuck with vibrate, you'd know the call was for you without (1) everyone else knowing it too or (2) advertising that you've got your own ring. Which, of course, goes back to the "I'm important enough for everyone to notice" point you made. I carry two cells on my belt and (every couple months) a pager. One cell is personal. The rest of the gear is work. It's all on vibrate. Mind you, sometimes I have the "which one is it" routine that everyone who is playing "Ode to Joy" on their cell has in a restaraunt, but what the hey...I know it's me, and nobody else does. :)
What is your Slash Rating?
True. all you do is have to create some false echo to the phone and/or tower that will disrupt or drop the call. But not only don't you have an FCC license, you are now messing with the cell phone companies ability to generate revenue. I see lawsuits raining down like frogs and locus during the apocalypse from the federal government, cell phone users and the providers themselves. Have fun. While I advocate the annihilation of cell phone idiots, not everybody is and it'd be your just desserts to get your ass sued off for using a jammer.
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I sincerely doubt, for example, that the author of this study took into account motion of the "point sources". Next time you ride a train, look at how people tend to rock back and forth as the suspension dampens the shock of rail joints and other track discontinuities. It's not much, maybe five to ten centimeters, but that's enough to cancel out constructive interference when the wavelength is only about 16cm.
This is why experimental science and empirical engineering are so crucial; they either confirm our understanding of the problem, or it's back the drawing board....
...-.-
In a small town in Connecticut, they put a cell phone tower in a church a couple years back. Since then, people keep mentioning ther've been less and less birds around, except for crows, who seem to have multiplied. I'm not saying there's any connection (and it's likely there isn't), but I wouldn't be suprised.
c-hack.com |
I guess will all start to develope NAS or the black shakes or whatever it was called.
The US FCC requires manufacturers to test the RF Specific Absorption Rate (SAR) on tissue. The FCC specifies a maximum SAR of 1.6 W/kg of tissue. All of the filings are available for public consumption at http://www.fcc.gov/oet/fccid/
t rieve.cgi?attachment_id=182858&native_or_pdf=pdf
Enter the FCC ID number from your cell phone (mine was under the battery) in the form, with the first 3 characters in the left dialog and the rest in the right.
This links to a list of filings for this device. Check the "Display Exhibits" and you'll see the SAR report for the device. For example, for the phone I have, the Kyocera 2255, this is the report filed for body-worn SAR:
https://gullfoss2.fcc.gov/prod/oet/forms/blobs/re
The data included has the power output and SAR at all of the different transmission modes for the device. Also, check out the neat-o plots.
Interesting that they have different permeabilities for muscle fluid and brain fluid, resulting in much higher maximum SAR for holding the phone to the ear (1.47 W/kg) than when its on the body (0.562 W/kg).
-molo
Using your sig line to advertise for friends is lame.
My cell phone (the ubiquitous Nokia 3360) is a TDMA phone that operates in the IS-54 (800 MHz) and IS-136 (1.9 GHz) bands. Now, 1.9 GHz sounds like a big, scary cancer-causing number. So let's see if it really is.
First of all, we need to know how radiation causes cancer. We'll just assume it's electromagnetic radiation, since cell phones definitely do not emit anti-protons, neutrons, muons and other shit like that. There's no way in hell a battery the size of a Triscut can generate reaction energies high enough to produce hadrons or leptons, so we can forget about them. (Well, actually, with a big capacitor you might get a few, but you're already getting showered with cosmic rays, and the pathetic little fart of hadrons you'd get out of a cell phone battery wouldn't count for didly squat.) The cancer-causing mechanism for electromagnetic radiation is fairly simple. In order to be dangerous, a photon (the electromagnetic force carrier particle) needs to carry enough energy to ionize (chemistry parlance for "fuck up") something important. It doesn't really matter how many photons you're slinging around, since it's the frequency that determines the energy of a single quanta.
So, what is our hypothetical candidate cancer-causing quanta going to have to inonize to do the deed? Well, DNA of course. It's going to have to cause a genetic mutation. Because of the way photons interact with matter, they are most likely to be absorbed by electromagnetically contiguous objects of sizes roughly equal to their wavelength. The reasons are deeper than this, but suffice it to say that a photon is "smeared" over an area about the size of its wavelength. Since you can't absorb part of a quanta (that's why they're called quanta, after all), you have to have a thing big enough to soak up a whole particle about the size of the wavelength. In this way, everything is, or is made of, antennae. To cause a mutation, you have to have a photon whose wavelength is about equal to diameter of a DNA molecule. Actually, the ideal length of an antenna is a quarter the wavelength of its intended optimal frequency, so we'll say the wavelength we're looking for is four times the diameter.
So, as I said, my cell phone operates at 1.9 GHz, or 1.9 billion cycles per second. What's the wavelength? Well, wavelength is the period times the speed of light. The period is the the inverse of frequency, so :
3*10^8 / 1.9*10^9 ~= 0.16 M
That's about the length of your hand, give or take a thumb. One quarter of that is about 4 cm - about the length of your thumb, give or take a nail. Now ask yourself this question: How big is your DNA?
If your DNA is built out of atoms the size of rasins, you might have something to worry about. The diameter of the DNA helix is 2 nm and the vertical rise per base pair is 0.34 nm. If you want a photon that will be able to reliably zap DNA, it needs to have a wavelength _smaller_ than 8 nm. The probability that a photon will be absorbed by a given object decreases with respect to the difference between the size of the object and the wavelength of the photon according to the standard deviation. So what's the probability that a given photon spewing out of my cell phone is going to fry some of my DNA? Well, we're a factor of five million away from the optimal wavelength. I'd say it's pretty fucking unlikely.
But wait a second - what's kind of radiation has a wavelength of 8 namometers? Well, we do the opposite to find the frequency :
3*10^8 / 8*10-9 = 3.7*10^16
That's in the ultraviolet range. Surprise, surprise!
So, what can we conclude from this? Well, since a cell phone has a transmission power of less than a watt and a wavelength the size of your thumb, it's not going to do jack shit to your DNA. Nada. Zilch. In other words, THERE IS NO WAY CELL PHONE RADIATION CAN GIVE YOU CANCER!!! I'd be more inclined to beleive that the plastic in the earpiece causes cancer.
You're several orders of magnitude more likely to contract cancer as a result of proximity to a 100 watt incandecant light bulb. It's got a much, much higher output, and its frequency range is thousands of times higher.
So relax, enjoy your wireless technology, and wear your SPF-30.
In spite of the suggestions and all the tests that I have made, I have not cavato a spider from the hole.
These were thought to be "wonder" products when they were introduced. Thalidomide was a medicine used as sleeping pill and Freon used to be the fluid inside refrigerator/freezer tubes. Then it was found after more than 20 years of research that Thalidomide caused birth defects and Freon caused the Earth's Ozone layer to thin out.
I'm not saying cell phones will have some detriemental effects but that people should be prepared to live with the consequences of their actions. Who knows, cell phone radiation may cause yet another malady still undiscovered.
Cell phone anyone?
Return the bells of Balangiga.
is in Japan. I don't know about the rest of you folks, but in the US and I assume in Europe there are few trains and they are full of people who either do not own these devices or choose not to let them be seen.
The most RF I've ever been exposed to was as the ALS in the Cobb Galleria convention center. All those geeks could fry chicken at 100 yards with their gadgets. Trains are pretty safe tho.
My $0.02 will always be worth more than your â0.02, so
You have the right to jam my cell and I slash your tires. We're all even, right? Actually, they DID take it into account. You know, the FCC rule that states 'this electronic device must accept any interference blah blah blah...'?
Speaking of the FCC, when did you licence your jammer for operation? That failed (multi billion dollar) business model has, and that's why I have a right to operate my cell and you don't. Legal speaking, your up shit creek. So no, you don't have a right to jam cellphones just like I don't have a right to slash your tires. Don't take my word for it, visit the FCC for details. Sorry fo ya.
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Yeah, let's fight back at the cell phone RF with more RF. Idiot.
Did he consider all the frontal-lobes absorbing the scattered EM radiation?
What area of the country are you in? I'm just curious because I use ATT Wireless in the Phoenix area and it's been nothing but perfect for me. In fact, a friend and I did a test a few weeks back and left our phones connected for over 7 hours =). I used to use Sprint PCS. There was no better day than when I cancelled that service.
No, sorry, that's not the only way in which physical or chemical agents cause cancers. DNA damage and mutations arise in our cells constantly and spontaneously. We wouldn't be able to survive if we didn't have a variety of biological mechanisms for repairing the damage and for killing pre-cancerous cells. Non-ionizing radiation may disrupt or alter inter-cellular signalling and thereby interfere with those mechanisms.
I've heard this kind of stuff over and over again - and alarmingly often from people who ought to know better (physics teachers, engineers, et cetera). The next time someone starts to tell you about cell phones giving you cancer, here's what you should tell them.
Physicists and engineers should practice a bit more humility when it comes to biology because most of them just don't have a clue (as your posting demonstrates).
Actually it's another reason to stay the hell off of trains.
Using the eqn for depth of penetration, it can be shown that cellphone EM radiation doesn't even penetrate a person's skull (in significant amounts).
... please explain to me how cell-phone radiation causes brain tumors. It really would interest me to know. (Don't bother to reply if you are not educated in the ways of EM)
BTW, future cellphone technologies use an even higher frequency, and thus penetrate even less.
So
Our bodies have not evolved to fly. If we were meant to fly, we would have wings.... So lets shred the airplanes.
Our bodies were never meant to go faster than 20 mph, so lets put speed governors on cars and trains (and boats).
Our bodies have not evolved to swim, otherwise we'd have more lung capacity. Thus having a swimming pool should be a capital crime.
Our bodies have not evolved to use keyboard, so why on earth are you posting on Slashdot?
Our bodies have not evolved to use cell phones.. So what? Nothing is consequenceless.... Cellphones, like planes and cars, offer convenience and productivity advantages; the question is are they worth the price.
Sure, there are negatives, but do the negatives. (What, *MAYBE* a few brain cancers after 20 years.) outweigh the advantages?
It's a joke. It's funny, laugh. Get a sense of humour. If necessary, replace ATT with Verizon or Sprint or whatever other wireless provider will get the idea across that wireless service sometimes sucks.
why not an intelligent jammer? it could detect that a cell phone is trasmitting nearby and start trasnmiting at the same frequency. the cell phone user will stop trying after a few minutes, the jammer will return to listen state, and the overall radiation will also goes down, until the next user tries... perhaps is not all that dificult to modify an old cell to do this...
First off, cellphones are in the 800 Mhz. band, "A" and "B" segments, I am not going to cover those portions here.
Pagers operate at several bands, most notably here are the VHF band/s at 150 Mhz., UHF band/s at 450 Mhz., and the 900 Mhz. band, like 929.7375 and so on.
I have never seen ANY pager on the 220 band in my state, so I can't claim they do not exist, but since the 220 band is carved up into business land mobile use, amateur radio and other government "services", suffice it to say that cellphones are not bothered by pagers or any device/s in the 220 band segment either, so designing a "jammer" for those frequencies would be a waste of money and time.
Now your cell jammer would have to be designed to be fully autonomous in nature, tri-banded and use antennas that are designed for tri-band phones so the effective radiated power is not wasted heating the coax, but is actually being radiated by the antenna.
Simple procedure if you are desirous of interrupting AMPS phones, but GSM, PCS and all TDMA, CDMA modulation types will take high cost equipment to "cheat" the built-in logic of the hardware, this is not a simple diode snip of a scanner here, but full-blown engineering challenge/s to the not so faint-of-heart.
My IFR 1200 super S does not have all I would need to even begin the process, but I can scan the control channels of AMPS towers and get the block assignments of those towers so I can punch in the frequencies, attach my 4 stage PA to the output and have at it, but why, for what gain do you achieve here?
Does anybody really think that the temporary blockage of a call is going to do anything here?
If you do succeed, they will just try again, and probably at a time even more dangerous to those around them!
People are too self important to think about their neighbors, they assume the world revolves around them alone, hence "your" courtesy is "supposed" to be for them, and them alone.
Simple solution; slow down in front of the car phone user, and if slowing to 40 doesn't get their attention, try some other form of rolling barricade, it works for the police.
Have your buddies go with and look for those cellphone users and then motion for everybody in the group to box in and slow down, that driver until they hang up the phone and pay attention!
Sure, they'll probably call the cops, but YOUR plea will be for the safety of ALL the vehicles on the road, you were simply attempting to prove to one driver that they are too distracted and you were simply trying to make them pay attention to the road(which you too are on).
If that doesn't work, file a complaint with the officer, state she/he was driving erraticly and you wanted to "assist" with keeping the roadways safe by gaining his/her attention, maybe the cop might thank you for being a "concerned" motorist and even win you a few "brownie points" as well.
In conclusion, jammers are not worth the money, time and effort for simply stopping a call, it's a burden on your resources, not the caller's.
You could also buy an ESN reader and clone the ESN and set them up to autodial all over the county, but this is again, an AMPS thing, not TDMA, CDMA or GSM, PCS "solution".
*CNN today reported that there is a new fad hitting the highways: CELLPHONE WAR DRIVING is the rage in California as drivers are trying to jam stupid cellphone users distracted by their use of their phone while enroute to work, school or soccer practice. Motorists are modifying their phones so they can transmit a signal that will jam the other motorist's cellphone during a call.
Oh well, I can dream of the fun, can't I?
206.39.38.2, DDN-BLK-36, DOD NET INFO CENTER. 800.365.3642 206.36.0.0-206.39.255.255 NET RANGE.
Yeah I did skip over that a little bit.. I guess the point is that UV contains enough energy to break molecular bonds, but not nuclear bonds, so you don't end up with a ion, but you do end up with broken molecles. If the cell doesn't die completely, and part or all of the RNA was affected, then it could incorrectly reproduce (aka mutate). Normally this condition is dealt with by the body and the cell is killed off. If and when it survives, and lives to create more copies of itself, then you can end up with cancerous cells.
However, microwave radiation sits between radio and visible light, so it seems logical that if visible light doesn't break molecular bonds then neither should microwaves.
If you don't really know what's happening inside a black box, you don't really know what will affect it, and how severely.
You are theorizing that there won't be any effect to be observed. This is nice, but needs to be backed up by experiment. But the experiments have been equivocal. So people reasonably don't know what to believe. (As far as I can tell, the experts don't know either. They've got theories...)
When people suspect that something might be dangerous, especially dangerous to their children, then it is quite rational for them to campaign to do something about it.
You may think that they are being silly, but as I read the evidence, it's uncertain. What you could establish are limits as to how powerful an effect it is. But that gets a bit hard to explain. (Yes, it's a weak effect, if it exists.)
Another problem is that many medical problems only happen after a significan time delay. If it's a weak effect with a ten year delay, I don't think any of the experiments so far would have detected it. Even if it eventually (say 30 years) resulted in 100% mortality. You can say that "No theory justifies that!", but theories are made up to explain results. If this effect is detected, a theory will be created. (I've already seen one about electron passage through membranes being affected because a moving electron generate a magnetic field and this causes it to move in a circular path, so fewer electrons get through the membrane and more positive ions get through (they're more massive, so they are less affected. There's a lot more to is, check the recent New Scientists [or Science News] issues.)
I think we've pushed this "anyone can grow up to be president" thing too far.
My Nokia 3360 itself generates enough EMFs when it rings to make my monitor look like it's degaussing if the phone is placed near it, and if the phone's in my pocket with my discman, when it rings there's enough interference in the headphones to not be able to hear the music.
It's a wonderful little phone as it doesn't have an antenna to break, and is tiny without being impossible to use, but I seriously wonder just how healthy it is to have this phone. Receiving calls when it's against my ear already just scares me.
Roll of aluminum foil ($10.00). Just put some over your head each time you want to use or are near a cell phone.
The day Microsoft creates a product that doesn't suck, it will be known as the Microsoft Vaccuum Cleaner!