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Re: Health Risk from Cell Phones.../ hands freeNTR
Posted By: Lee In Response To: Re: Health Risk from Cell Phones.../ hands freeNTR (rabbit)
Date: Thursday, 24 July 2008, at 8:09 p.m.
Now, you guy's have me going on this.
Had a bit of a handle on some of this back in the 70's working on the first B1 bomber, with all of the radiation requirements.
The short book:
All of this is the same - alternating electric/magnetic fields, commonly called radio waves.
What varies is the frequency (hence wave length) and the power level (often called energy level) especially when talking about x-rays, gamma rays.
The power level (energy) has more to do with potential "damage" to human tissue, the frequency has more to do with just how it is absorbed (or passed through) human tissue - e.g. its effect on cells.
You just mentioned "portable phones", same idea, as well as that wireless router possibly sitting on your desk.
Then we have the tv's and computer crt's.
All are sources of electromagnetic radiation.
Lets start with the micro-wave oven. I accept Seall's number of 2.4 ghz for the frequency (don't know/recall) but doesn't matter much for this discussion.
- The miro-wave oven is fairly high power and shielded (from we human users). What makes it work (recall that you need moist food (water is a dipole - like a little magnet). The Frequency results in a wave length about the size of a water molecule (a dipole with a N and S pole). The varying micro-wave signal shakes the living crap out of the water molecules and friction among them results in the heating.
- Put a dry piece of bread in a micro-wave - nothing happens.
-The holes in the "see through" door of the micro-wave are of such a size that they are an effective "short circuit" for the radiated signal (gets into transmission line theory) but the net result is the energy/signal does not escape from the oven, and cook we human users.
The hot filament of a Tv or Crt electron gun - used to generate the beam for illuminating the screen is capable of generating X-rays. An old problem years ago when the repair guy could boost the voltage to improve a weak picture - the higher voltage resulted in harmful X-rays being emitted do to the "higher power" level.
Are the effects of all of this "well understood". NO !!
Early standards (maybe even today) hinge on the notion that the emitted radiation is much, much less than that would be received from our normal environment (i.e. outside in the sun) for the typical periods of time most humans are out there.
- This is commonly referred to as "natural background radiation".
I have not observed too much concern on the radiation from portable phones or wireless routers(the 2.4 ghz is apparently the same as a micro-wave oven, but the power level is much lower).
- Newer portables are 5.8 ghz [those that do not interfere with the wireless routers] and older ones were around 900 mhz.The power level of a cell phone is considerably higher (and I do not know the frequency).
So the potential for the cell phone to be more harmful, if only do to the transmitted power level is certainly there.
- i.e. need to hit that tower maybe a mile or more away (not typical of a portable phone.)- Is it a realistic worry, I do not know. But will look further.
There are some that believe that close proximity to the high voltage power transmission lines (only 60 Hz.) but high field strength is a problem. I do not know.
All the TV and Radio station transmissions are way, way down there compared to all that is floating around in your front yard.
Any way, this is the drift of the issue.
Lee
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