Bob Kupps wrote:
> So I modeled a half wave dipole in free space and sure enough the wire
> segments on each side of the feed point carried equal current. I then placed
> a resistive load at the center of one half-element (to simulate? a lossy
> "return") and now see that those segments no longer carry equal currents,
> with less current on the side with the load. Can someone please explain this?
>
>
>
You are misinterpreting what you are seeing. When you put a resistor in
one side of a dipole you modify the current distribution in both sides
of the dipole and the side with the resistor has a large decrease in
current at the point where the load is located. So the current
distribution is considerable different in the two halves of the dipole.
The source is at the center of a segment. Since you can only measure
the current at the center of the segments adjacent to the feedpoint
(that's one segment away, on each side, from the feedpoint) the current
will be different. That one segment difference away from the feedpoint
is enough to show a difference in current. If you want to see the
current at the feedpoint use the "Src Dat" tab. It only lists a single
current because it's the same in both sides, except 180 degrees out of
phase.
It's impossible to violate the law stated by Tom. If you want an easy
way to test this, wire a battery to a bulb, measure the magnitude of
current out the negative terminal of the battery and then measure the
current out the positive terminal of the battery. If you don't get the
same answer, you have a measurement error.
Jerry, K4SAV
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