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Re: Some more Questions on RF Interference and others
>
> With the power of your unit, I don't think you will bother neighbors
across
> the street.
>
> > 2) Can a faraday cage be made out of the wire used for bird cages? or
must
> > it be a more fine mesh of wire? Also can the frame be made out of
> > wood/plastic?
>
> I have heard that the mesh size should be smaller than 1/4 of the
wavelength.
> In other words, just about any size mesh will do for a TC(assuming what
I
> heard was corrrect). Wood framing will be fine. Just ground the cage.
One
> way to find out is to use a battery powered AM radio and see how far the
> interference can be picked up while your coil is operating.
Perimeter of any hole should be less than 1/2 wavelength (i.e. the mesh
size should be < 1/8 wavelength). For TC, chainlink fence is small enough,
however..
Any wire or conductor which penetrates the hole provides a path for EMI to
get through. Woven wire (like chain link fence or woven hardware cloth or
window screen) has zillions of wires going from the inside to the outside,
and hence lots of paths for interference. You need welded mesh. The stuff
they use for reinforcing concrete works nicely at low frequencies, even if
it is steel and not copper or aluminum. ALuminum window screening, btw, is
terrible. Not only is it woven, but the oxide layer on the aluminum means
that there isn't a good connection at the cross overs, so it really has
little wires running from inside to outside without interruption.
Watch the power leads and control leads running in or out of the faraday
cage. They will provide the "best" path for EMI conduction, most likely.