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Comment Re:Actually. . . (Score 1) 189

Modulation methods are for the most part very complex in modern cellular phones and so to say that they only contain components in the lower portion of the audio spectrum is just being ignorant, is this what you were meaning? Power levels in the range of +35dbm at frequencies above about 30MHz will cause small amounts of heating and if the RF is concentrated into a small area (like the end of a piece of unterminated feedline) will cause intense heating to occur. That heating is directly related to power level, frequency used and dielectric properties of the item being exposed to the RF energy. That is why microwave ovens works so well, because the frequency being used (2450MHz) happens to excite water molecules well and so quickly heats the food in the transmitter 'cavity' in this case the microwave oven, also the oven is emitting an order of magnitude more power. The average cellphone emits only about +22dbm (150 milliwatts, .15 watts) whereas a microwave oven emits about +62dbm (1500 watts). As far as the 'self calming', it mostly has to do with my basic understanding of radio electronics and RF field strength through personal experimentation and also theory gleaned from education and text books, it is very well documented and should be clear to anyone who will take the time to educate themselves about radio frequency energy. As I have been involved in the industry for well over 35 years (I am only 50) and have had no adverse health issues, I would say that I can feel some level of 'calm' in my knowledge of the possible health effects from exposure to low level and high level RF energy. But with that said, I treat my whole life with a healthy dose of skepticism and am open to reasoned research that can prove that I should totally eliminate all the electronics that is around me, the jury is still out imho...

Comment Re:Actually. . . (Score 1) 189

Well, actually you might be confused, I did not say that non-ionizing radiation is safe. but AT THE POWER LEVELS AND DUTY CYCLES BEING USED it is safe. Yes, as a matter of fact you can get burned with non-ionizing radiation, I have many long term RF burns on my fingers to prove it (I work with radio frequency transmitters as a hobby and as a professional). But only with much higher orders of magnitude power levels and "on time" (duty cycle) RF radiation can be dangerous, but it gets more complicated than can be explained here. Also the frequencies and modulation techniques that are being used with modern mobile phones by their nature (very low power and duty cycle) cause them to be much less a threat than (again) exposure to the sun which is a much broader spectrum and higher duty cycle. Also you seem to confuse extremely low frequency energy "1Hz to 500Hz range" with the much much higher frequency (800 to 1900MHz) that Cellular and PCS phones use. There may be certain effects from the very low field strengths emitted by mobile phones but it really is minute. I actually tend to be concerned about the exposure we get to high level EMF from power lines myself but I don't have enough information to feel informed. Finally I try not to be scared by science but instead keep an open mind and realize that there is allot I don't know but also quite a bit I do know and can learn, I will consider what you have shown above but will keep in mind what I do know...

Comment Radiation yes, but non-ionizing radiation folks... (Score 5, Informative) 189

Folks please don't get wound up about 'radiation' from a wireless device, remember that it is only 'heating' radiation, not ionizing radiation http://en.wikipedia.org/wiki/Non-ionizing_radiation. All it is going to do is warm your skin near where the phone is, or very slow cook for you microwave oven enthusiasts... Ionizing radiation like gamma rays are quite another story and will cause DNA damage, but are a wholly different type of 'radiation'. You will get more damage from standing out in the sun every day then you will from the weak signal that is emitted from your mobile. Now the fact that most mobile phones these days do not have a very efficient antenna is quite the reason that so many of them have such bad SAR values, if people could just stand having a little 'duckie' antenna sticking out of the top of the phone then we would have more efficient emission of the signal and a better SAR value. But that is not sexy and so we won't see any more antenna's like we did when cellphones first came out and so instead the phone body itself is the antenna and a good portion of the emitted signal is absorbed by the hand and head, its just the way it works... The best thing is to educate yourself and make your own decisions http://en.wikipedia.org/wiki/Mobile_phone_radiation_and_health

Submission + - Ask Slashdot: Geek travel to London from US, tips? 3

Audrey23 writes: I am traveling to London from Washington state for two weeks in December for pleasure (use it or lose it vacation scenario) and was wondering if I should bother bringing my laptop?
I know that I would have to change the region code on my wireless amongst other things and the power cord would have to be changed for a UK outlet.
Would I be better off not bringing my laptop and just using Internet kiosks (do they exist in London) or would having my laptop be a better choice to keep in touch, off-load my digital images etc?
I plan on hitting the British Museum but was wondering what geeky things to do that are in London that might be worth going to and any tips hints on overseas travel for geeks?
I travel quite a bit in the states but this will be my first trip overseas and want to make the best of my stay in merry old England.
What words of advice do you travel seasoned geeks have for me?

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