From: Juan <juan.g71@gmail.com> On Fri, 18 Sep 2015 16:24:20 +0300 Georgi Guninski <guninski@guninski.com> wrote:
Once upon a time, at an open source party some people claimed that from commodity microwave oven one can made device that (don't remember which of those) damages electronics and/or severely interfere with GSM communications at nontrivial distance. shouldn't an unshielded microwave oven jam a whole city as well as burn anybody who gets close to it? looks like a great 'terrist' project.
Within the last couple of months, I think somebody was arrested for planning some sort of "X-ray death ray". http://nypost.com/2015/08/18/kkk-member-built-death-ray-machine-to-kill-musl... But only a dweeb doesn't know that X-rays cannot be focussed. (With one very obscure exception not applicable here. Find it and get an "attaboy!". ) Microwaves, OTOH, can be focussed rather easily. The frequency is 2.45 Ghz, at about 1 Kilowatt. (wavelength about 12 centimeters.) I'd have to consult a Radio Amateur's handbook, but a modern dish (intended or Directv or Dish network) could probably get 15-20 db of gain, compared with isotropic. An old-style 8-foot dish probably would do 30 db gain. That would be 100 kilowatts ERP. Such an unshielded (open) device would probably impair WiFi at 2.5 Ghz severely, if you're close to it, say a few hundred feet away. Fortunately, I think microwave ovens have better than 60 db of shielding. A few 10s of feet, away, hardware damage might occur if that full 1 kw were allowed to leak out. Jim Bell
Don't remember the electricity requirements. ordinary requirements of an ordinary oven? Ordinary microwave ovens are probably 75%-80% efficient. Thus, if you need to supply a 1 kilowatt microwave, you'll probably need 1250 watts of AC power.