[Message bounced the first time, permanent fatal error on the Vortex
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Michel Jullian wrote:
----- Original Message -----
From: "Stephen A. Lawrence" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, October 25, 2007 2:40 PM
Subject: Re: [Vo]:Re: "Cold" electricity
Horace Heffner wrote:
...
Good point. Another option along the same lines might be to simply strip
a section of the ground wire and connect the ground wire to the faraday
cage at the entry point using an alligator clip. It the lights go out
then the power is from an external source.
Wow, that's perfect!
Now why wasn't this obvious to start with? Dunno -- maybe it was to
others, but it sure wasn't obvious to me, at least.
Maybe an old fashioned pressure cooker would make a nice Faraday cage, the
vapor outlet hole could serve to let the wire in...
I think it has been stated in a variety of ways by a variety of people
(Terry, Bill...) that the Faraday cage should be grounded, I can hardly
believe this hasn't been tried yet...
Sorry to be contradictory, Michel, but that is almost exactly the
/opposite/ of the point raised by Horace.
It doesn't matter whether the cage is "earth"-grounded or not; the earth
ground is a red herring. The point is the circuit inside must be
connected TO THE CAGE, not (solely) to an external ground, and must be
tied to the cage by a wire which is internal to the cage, not by a long
looping external path.
Earth-grounding the cage makes it impossible to "see inside"; a grounded
cage blocks all electrical fields inside from escaping. An ungrounded
cage does not. But, conversely, an UNgrounded cage blocks external
fields from entering the cage just as well as a grounded one. In this
case, that's all we care about, and the "earth ground" of the cage
doesn't matter. (Does the pie plate turn transparent when the ground
wire is removed? Visible light is, after all, just high frequency EMR
-- or at any rate it can be so modeled when attempting to understand its
interaction with a conductor.)
If the cage and the circuit are tied to "earth ground" SEPARATELY then
the area of the loop made by the (separate) ground wires acts as an
antenna (obviously!) and the circuit cannot be said to be "grounded to
the cage" in any useful way. Until now, that sort of "grounding" is all
that had been mentioned, and it is all that has been done, as far as I know.
Until Horace's post, no-one, as far as I know, had suggested tying the
ground wire from the circuit directly to the cage, so the circuit was
"grounded to the cage" by a conductive path which was contained entirely
within the confines of the cage itself.
Michel
