[geekmaster]

Time for a little "on topic" discussion:

Originally Posted by shidunce

... its really unhealthy to have wireless router in your apartment. Same to DECT phones.

Umm... Really? "Extraordinary Claims Require Extraordinary Evidence" -- Carl Sagan. Where is your "extraordinary evidence" (not the "we don't know" kind)?

And here is Carl Sagan's acclaimed original source (a very interesting read on pseudo-skepticism):
http://www.anomalist.com/commentaries/pseudo.html

Originally Posted by shidunce

geekmaster,
Thank you for your reply)
I work for money, measuring levels of radiation in work places and private places )

Okay, thanks for this disclaimer. This shows that you have an incentive to show controversial information with a view biased in favor of your source of revenue. We can use that to help determine the veracity and balance of your claims.

Originally Posted by shidunce

First of all I want to say that I divide radiation from all applications into three big categories:
1) Low frequency Magnetic field (from 1 to 100 000 hz) power lines, wiring inside houses, motors. Measured in mili Gauss or nano Tesla.
2) Low frequency Electric field (dirty electricity) - wiring inside houses, many many other applications (from 1 to 500 000 hz) Measured in Volts per meter.
3) High frequency radiation that comes from All wireless applications, cellphones, radars, radio, etc.

You can receive EM energy with an electric field dipole antenna, or with a magnetic field loop antenna. They each have strengths and weaknesses depending on your application. Electric antennas are preferrable for high frequencies and magnetic antennas are preferrable for lower frequencies, due to the size and mass of an antenna relative to the wavelength of the target frequency (frequency is the inverse of wavelength). Whichever antenna is smaller/lighter/cheaper is generally preferred for most applications for receivers, but transmitters usually use electric antennas. You include "radio" as "high frequency", but in reality radio includes ELF and light (both of which are just different radio frequencies). All frequencies of electromagnetic radiation contain an electric component and a magnetic component (as indicated by its name). Both fields must be considered INDEPENDENT from the measured frequency. This makes your claims above not quite accurate and somewhat incomplete.

Originally Posted by shidunce

1,2 kinds vanish fast with distance, but third kind is not vanishing. Its so called filling radiation - it reflects many times from walls, metals, etc..

ALL kinds of EM radiation (including visible light, infrared, heat, and broadcast radio) expand in a spherical wavefront from each distributed point source of the radiator (transmitter antenna). Taking a single point source into account, an emitted wavefront will expand at the speed of light (adjusted by the propagation velocity of the carrying medium) in a perfect sphere, with the transmitted power distributed evenly over the surface of the sphere. Because the surface area of a sphere is proportional to the square of the diameter, the power per square meter also diminishes at the square of the distance. When the radio wave has travelled so it is 100 times as far away, its strength is then spread over a surface area that is 10,000 times larger, and hence the Watts/sq-m has decreased by a factor of 10,000. This is irrefutable pure physics and mathematics. Walls completely absorb some radio wavelengths, and are completely transparent to other wavelengths. They only reflect radio waves (as claimed) if they are covered with a metallic surface such as aluminum paint (but radio waves can bounce off other metallic objects in the room). The claims made above are clearly false.

Originally Posted by shidunce

The only thing that can catch it in modern cities is human body. OK, some plants, water too

Most modern cities contain radio and TV antennas, and satellite dishes and numerous other antennas. They can certainly "catch" radio waves. Depending on frequency, different (non-metalic) materials either pass or absorb EM energy. It just so happens that a water molecule has a resonant frequency of about 2.4GHz, which is WHY it absorbs/blocks wifi signals (and why it works in microwave ovens). Super high frequencies (like radar) behave much like visible light and are blocked by most things that block light. ELF passes easily through water/stone/earth, which is why it is often used for submarine and subterranean communications. High frequencies (like AM radio) easily pass through buildings and trees (which can block FM in some cases, and block UHF TV signals even more).

If you study antenna design like I did, you can shape radio waves by using a reflector element that is slightly longer than the wavelength, and direct (focus) radio waves with a director element that is slightly shorter than the wavelength. You can see that principle in action on old-fashioned TV antennas. You can also reflect and focus radio waves with a parabolic reflector. In the case of microwaves, you can even focus them with a lens that is made of paraffin instead of glass, or with a zone-plate antenna that uses the same diffraction properties as light, but at much longer wavelengths.

The reason I am providing this information here is to show that your claims are stated as facts, but they are in conflict with the real facts such as those that I provided. You are free to continue to believe your "facts" if you wish (as they are part of a belief system common to pseudoscience), or you can research the real facts that I have provided by googling some of the keywords.

Regarding RF propagation, I recommend reading the ARRL Antenna Design books. There is plenty of wifi antenna design on the net too.

Of particular note is that these antennas "catches" radio waves, and its ingredients do not contain humans, plants, or water (contrary to a claim made above by the OP). But water could be used as an RF shield (in fact, rain can reduce microwave reception because of that fact).[/COLOR]