Re: Faraday Cage and 1/4 wavelength sized holes

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <dhmccauley-at-spacecatlighting-dot-com>


For a Faraday cage to work for some frequency, then the holes in that
faraday cage must have a diameter less than the 1/4 wavelength of the
frequency you are trying to block.
If you build your faraday cage out of chickenwire, sure it will keep in your
arcs and lower frequency garbage, but the higher RF frequencies (Ghz) will
pass right through it.

Dan




 >  > Regarding all of this cage design, about what frequency does RF become
 >  > highly directional (like microwaves)? Would coving the floor be
relevant?
 >  > Will the RF simply radiate toward the floor and the earth underneath,
 >  > without curving upwards into the house (or horizontally and out into
the
 >  > neighborhood)?
 >
 > If you want a frustrating experiment with a Faraday cage, exactly in
 > frequencies close to microwaves, put a cell phone inside a microwave
 > oven, close the door, and call it. (Of course don't turn the oven on!)
 > I wonder if the oven keeps its own radiation inside...
 > My experience with sparks and Faraday cages say that they are not
 > effective to completely block irradiation. Maybe they simply don't react
 > fast enough. A perfect Faraday cage would require perfect conductors,
 > without resistance or reactance. You can eliminate resistance using
 > thick wires, but there is no way to eliminate reactance, inductive
 > reactance specially.
 >
 > Antonio Carlos M. de Queiroz
 >
 >
 >
 >
 >