David VanHorn microbrix.com> writes: > > > David VanHorn microbrix.com> writes: > > > It is possible that the 3mm microwave could be > > > blocked by something as simple as a wet (with salt water) neoprene > > > wetsuit. > > Wasn't me what said that.. > > It does seem that the microwave field would be easier to > shield/disperse/absorb. > I wonder what a meter square of velostat foam costs these days. I posted the part about the suit. To simplify, it works like this: any material has absorbance and reflectance. These are reciprocal (absorbance + reflectance = 1). Reflectance is not 1.0 therefore even a good reflector will absorb some. That will heat it up. Therefore it should not be directly close to the skin. A layer of air (or dry clothes) underneath should allow it to get nice and toasty without bothering the wearer. Iow, normal clothes outside, a vest or poncho made from a survival blanket over that, and thin clothes outside. Iow, back to thermal blanket ponchos, and go take out the deathray. Of course I haven't tried this ;-) Now the wetsuit: What they seem to be saying is that they produce an irradiance that is about 5 to 10 times the sun's. The sun produces about 0.1W/cm^2. So they produce about 0.5 to 1W/cm^2. If someone wears a wet wetsuit and it absorbs all the radiation then it takes about 4Watts per degree per gram of water in the suit. Assuming 0.5g H2O/cm^2 of suit and 30 degree rise toleated (remember the suit is an insulator) it should take 60 seconds for things to get toasty. That's enough to load a RPG and fire it even if standing in one place. Of course nobody walks around in a wet neoprene suit. This was just to show the idea. In general the 'death ray' systems were not so good so far. That means since Archimedes and till today. Even the Nautilus system is not yet operational afaik. And the system will need power. 10 square meters covered at 5 times sun is 25kW out (probably 50-100kW in). Add losses, efficiency, atenna etc and you have a 100kW/140HP generator running somewhere. The trick with irradiance weapons seems to be that they heat only the outer layers of the skin rapidly. They are not powerful enough (yet) to heat the whole sausage. Because they heat only a thin layer of skin they can use lower power. Therefore spreading the power out quickly (in depth or in mass) alleviates the problem. They say that tests showed covered people not to have problems, excepting the parts which were not covered. I'm pretty sure some sort of countermeasure will be devised. That will limit its use agains civilians. Together with water hoses and tear gas. Presumably some of the civilians such exposed will join the opposition after that. Especially after some relatives of theirs will get injured or killed by the 'nonlethal' systems. Peter -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist