Electromagnetic weapons: power? I essentially have three questions concerning weapons based on EM waves or more generally.


*

*Focusing on the weapons using radio-waves and/or micro-waves, what power do these types of weapons need to radiate to generate the described effects?

*How easy or difficult would it be to make your own weapon or to acquire one. As I understand it from the wikipage, only the US army is known to have such weapons, so I suppose it is not something you could easily make unless you have a physics lab at your disposition.

*We live in a world where the "amount" of radio-waves and micro-waves that pervade our space is impressive. Isn't there any danger to be expected from these waves, considering that weapons can be built based solely on concentrated pulses of EM waves? Could something apparently as benign as a cell phone or a WiFi connection have the same effects, even though they would require longer exposition? I am aware that studies, also this link and this one, have been done, and they seem to be either inconclusive or answering in the negative. Yet, I have this nagging doubt.
I am aware that the question is bordering on questions of medicine and physiology as well as engineering rather than pure physics, but I'm not sure where else to ask.
 A: *

*Minimal required energy starting from 100J in ns-scale pulses, any kind of microwawe/light will do. It would be Very hard to deliver energy to distance > 10m. In constant emission you would need power in the range 100-1000W+ to see minimal effects.

*Russia also had laser weapons, but they are not widely used (basically because conventional weapons are much cheaper with the same effect). Well, you can make 100W CO2 laser at lab or 1000W microwave emitter, but it's not really useful due to short range. Conventional weapons are really much more efficient for the price.

*Amount of energy is to low (constant emission <1W). 
A: Search for the patent for an electromagnetic weapon in a 500lb dumb bomb form factor. It will give some insight but not performance parameters. The effectiveness of the weapon is not intrinsic to the weapon. It also depends on the vulnerability of the target.
EU technical commissions have been working on IEC performance requirements and measurement methods for EMP for non-military equipment for a while now in anticipation of an EMP event.
