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Re: Faraday cage




>From: David Trimmell <dwt-at-efn-dot-org>
>To: tesla-at-pupman-dot-com
>Subject: Faraday cage
>
>Hello all,
>
>I am needing to build a Faraday cage to hopefully reduce the 
>interference my coil causes with my telephone and the AM radio reception 
>around my house.  No neighbor complaints, but just encase the FCC is 
>listening.  My question is: how fine of a wire mesh would you need to 
>block the RF from a coil running from 200 to 350 kHz?  And the 
>associated "noise"?  I was thinking of trying Aluminum foil strips, but 
>then was thinking of the grounded capacitance around my coil, as the 
>basement room I have my coil setup in is not to spacious.  So I was just 
>interested in what creative designs some of you may have come up with?
> Thanks for any input.
>
Dave,
	From old memory: you need to keep the "holes" in your 
RFI shielding under 1/10 of a wave length. Given lamda=300/(f in
MegaHertz) lamda=857 meters. divide by ten, and keep the mesh below
85.7 meters between wires;)

Since your TC is under the ground level, you may not be radiating
anything out to your neighbors, except by the power line. Without a
signal strength meter though, you may not be able to measure it and
really find out.

Try some 0.1uF caps across the phone lines and power lines. Use 250V
or better for the phone and 600V or better for the power.


thoughts and comments always welcome.

jim