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Date: Thu, 05 Nov 1998 16:24:21 -0800 From: Michael Motyka <mmotyka@lsil.com> Subject: Re: How to test *your* microwave oven distribution pattern.

Wrong metaphor for RF energy.

You said more than you know with that one.

It's not water. A ground is not a storm drain.

From the perspective of the flow of charge that is a very good metaphor. Charge flows from the high charge area to the low charge area *always* and ground is by definition the lowest charge area there is. Just like water *always* flows from the high PE to the low PE.

Imagine two conductive spheres ( earth and moon ? ) and an RF generator in a box sitting *peacefully* in space. Classical 3-body problem.

That's gravity, not electrostatics. There are no intractable problems regarding n-body electrostatics issues as there is with gravity. Now of course in the real world we can't get one without the other, but you didn't mention that aspect.

The DC potential that exists between any of them has absolutley no effect on a wave travelling anywhere

DC potentials have no effect on a wave anyway, they don't emit photons. They are a physical representation of a line intergral. The potential between two points is not effected by the path taken to get between the two points.

( unless you want to get into the topic of nonlinear materials ).

Bullshit.

So forget about everything in the scene except that generator in the box.

Then why in hell did you bring it up in the first place. I smell spin doctor bullshit coming....

Shielding consists solely of preventing the wave from getting out of the box into free space where it can be detected. There is nothing special about *any* of the DC references.

There is no wave with DC. If you want to make a wave you have to *move* the DC field generator or the measurement device. Now the charge that is *in* the box will leak to the outside of the shield *even if it's an insulator*, it's called charge tunneling.

Earth may be special ( source of women and beer ) but not to a wave.

Depends on a wave of what. If we're talking electrostatics then yes Earth is special. I would direct you to many of Nikola Tesla's work on this exact topic but you probably wouldn't read it. It's special because the Earth itself has a charge and that interacts with the charge on the box. If the charges are opposite they attract and the box moves toward the Earth (the Earth moves toward the box as well but the delta rho is inconsequential so we usualy ignore it). If the charges are identical then the two move apart. ____________________________________________________________________ To know what is right and not to do it is the worst cowardice. Confucius The Armadillo Group ,::////;::-. James Choate Austin, Tx /:'///// ``::>/|/ ravage@ssz.com www.ssz.com .', |||| `/( e\ 512-451-7087 -====~~mm-'`-```-mm --'- --------------------------------------------------------------------