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Old April 10th 07, 12:07 AM posted to rec.radio.amateur.antenna
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On Mon, 09 Apr 2007 13:27:21 -0700, Roy Lewallen
wrote:

So, does the current go clockwise or counterclockwise? How much goes
that way compared to the radial component? Where can I find a
quantitative or explicit statement of your interpretation?


Hi Roy,

Probably in a library. Field work seems to resolve issues too. It
may even prove your speculation in contradiction to mine. Outside of
these authors, we both seem to be shy of "authoritative references" to
parse that Byzantine statement of theirs.

I can only further speculate that BL&H were remiss in specifically
quantifying loss (you aren't asking me for numbers you are already
aware of, are you?), while offering numerous formulaic relationships
of loss against many factors. If we look at their data and observe
that adding radials lowers loss, but not by any precise relationship,
are we left without quantifiable proof, or the obvious implication of
strong correlation? Was there deceit in their arriving at some
conclusions through inference? As Reggie would note, they didn't
actually measure earth at all! Such a retort was met with indignity
in the past, is it now their impeachment?

However, as to counter/anti/clockwise, What impels current to follow
any such presumption? There are two sides to every wire laying in a
plane and phase mappings for earth currents that are symmetrical about
them. To anticipate your challenging me on that statement (clearly
BL&H never, explicitly say this), I can only offer a modest sense of
observing the bleeding obvious. Myself, I don't find BL&H so obscure
to impose this remarkable characteristic that current leaves the wire
on only one side.

Brown, Lewis and Epstein were REPORTING, not inventing, nor offering
pedant readings of scripture. Scribes, such as we are, are free to
interpret within the bounds of their own data, assumptions, and
conclusions. I've offered mine that conforms to many of their points.
If you have your own, you must survive by the same strictures. Given
the specific contention, I am especially intrigued in how you would
answer why the current departed the wire, and where it goes in light
of a potential map created by the phase shifts.

73's
Richard Clark, KB7QHC
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Old April 10th 07, 12:42 AM posted to rec.radio.amateur.antenna
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Richard Clark wrote:
On Mon, 09 Apr 2007 13:27:21 -0700, Roy Lewallen
wrote:

So, does the current go clockwise or counterclockwise? How much goes
that way compared to the radial component? Where can I find a
quantitative or explicit statement of your interpretation?


Hi Roy,

Probably in a library. Field work seems to resolve issues too. It
may even prove your speculation in contradiction to mine. Outside of
these authors, we both seem to be shy of "authoritative references" to
parse that Byzantine statement of theirs.

I can only further speculate that BL&H were remiss in specifically
quantifying loss (you aren't asking me for numbers you are already
aware of, are you?), while offering numerous formulaic relationships
of loss against many factors. If we look at their data and observe
that adding radials lowers loss, but not by any precise relationship,
are we left without quantifiable proof, or the obvious implication of
strong correlation? Was there deceit in their arriving at some
conclusions through inference? As Reggie would note, they didn't
actually measure earth at all! Such a retort was met with indignity
in the past, is it now their impeachment?

However, as to counter/anti/clockwise, What impels current to follow
any such presumption? There are two sides to every wire laying in a
plane and phase mappings for earth currents that are symmetrical about
them. To anticipate your challenging me on that statement (clearly
BL&H never, explicitly say this), I can only offer a modest sense of
observing the bleeding obvious. Myself, I don't find BL&H so obscure
to impose this remarkable characteristic that current leaves the wire
on only one side.

Brown, Lewis and Epstein were REPORTING, not inventing, nor offering
pedant readings of scripture. Scribes, such as we are, are free to
interpret within the bounds of their own data, assumptions, and
conclusions. I've offered mine that conforms to many of their points.
If you have your own, you must survive by the same strictures. Given
the specific contention, I am especially intrigued in how you would
answer why the current departed the wire, and where it goes in light
of a potential map created by the phase shifts.

73's
Richard Clark, KB7QHC


Ok, I understand that. Your answers to the two questions I asked are
that you don't know and you don't know. In the absence of any evidence,
I'll continue to disbelieve there's a circumferential component of the
current.

Roy Lewallen, W7EL
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Old April 12th 07, 07:55 PM posted to rec.radio.amateur.antenna
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On Mon, 09 Apr 2007 16:42:10 -0700, Roy Lewallen wrote:


Brown, Lewis and Epstein were REPORTING, not inventing, nor offering
pedant readings of scripture. Scribes, such as we are, are free to
interpret within the bounds of their own data, assumptions, and
conclusions. I've offered mine that conforms to many of their points.
If you have your own, you must survive by the same strictures. Given
the specific contention, I am especially intrigued in how you would
answer why the current departed the wire, and where it goes in light
of a potential map created by the phase shifts.

73's
Richard Clark, KB7QHC


Ok, I understand that. Your answers to the two questions I asked are
that you don't know and you don't know. In the absence of any evidence,
I'll continue to disbelieve there's a circumferential component of the
current.

Roy Lewallen, W7EL


Roy, it seems to me everyone has missed an important point concerning a circumferential component of the
current.

We know that the current flowing on the radial wires is radial in direction. What seems to be missed is the
current that returns to earth between the wire radials. That current is going to flow in the direction of the
lowest resistance. As such it's not going to flow radially alongside the currents flowing on the wire, because
the radial resistance of earth between the radial wires is much greater than the resistance of the wires.
Consequently, currents reaching earth between the wires will find a lower resistance by traveling toward the
nearest radial wire instead of continuing in a perfectly radial direction. This new direction of current flow
will not necessarily perfectly circumferential, but will certainly be somewhere between radial and
circumferential.

Walt, W2DU
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Old April 12th 07, 08:45 PM posted to rec.radio.amateur.antenna
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On Thu, 12 Apr 2007 18:55:30 GMT, Walter Maxwell
wrote:

This new direction of current flow
will not necessarily perfectly circumferential, but will certainly be somewhere between radial and
circumferential.


Hi Walt,

So as BL&H report without too much pain:
at page 760:
"When the earth is of good conductivity,
the current leaves the wires and enters the earth closer to
the antenna than it does when the earth is a poor conductor."


Now, as to your comment
That current is going to flow in the direction of the
lowest resistance.


It is awfully damned hard to beat the least resistance path of copper
over earth. And yet BL&H offer us this observation I requote above.

What will trump a higher resistance path is greater potential
difference and proximity. Note that BL&H are quite specific about
proximity to the antenna, and hence it follows that the separation
between radials is closer there, than further out from the antenna.
Certainly I can find no where to quote this observation of growing
closeness from BL&H for Roy's consideration, but I trust my common
sense of geometry here too, and I will proceed.

BL&H report (without going into the how, or how much):
"From (8) [that formula] we see that the earth
current proper leads the current in the wires
by 90 electrical degrees."

such that at "that" radial distance, there must exist the greatest
circumferential potential difference between the wire and the earth
currents which is clearly mandated by phase. If a potential gradient
along the circumference is greater than that along the radial, and the
distance along the circumference is smaller than the distance along
the radial; then it stands to reason why BL&H even offer to comment
"current leaves the wire."

Current through earth is largely lost to heat although I do have a
fractal antenna that uses earth current to optimize its low angle
launch characteristics.

Ultimately this reduces to the rather pedestrian observation that more
radials closer in serve efficiency - observed and reported by BL&H.

73's
Richard Clark, KB7QHC
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Old April 12th 07, 09:53 PM posted to rec.radio.amateur.antenna
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Walter Maxwell wrote:

Roy, it seems to me everyone has missed an important point concerning a circumferential component of the
current.

We know that the current flowing on the radial wires is radial in direction. What seems to be missed is the
current that returns to earth between the wire radials. That current is going to flow in the direction of the
lowest resistance. As such it's not going to flow radially alongside the currents flowing on the wire, because
the radial resistance of earth between the radial wires is much greater than the resistance of the wires.
Consequently, currents reaching earth between the wires will find a lower resistance by traveling toward the
nearest radial wire instead of continuing in a perfectly radial direction. This new direction of current flow
will not necessarily perfectly circumferential, but will certainly be somewhere between radial and
circumferential.


Walt,

I hadn't missed that phenomenon, but didn't mention it because it
doesn't produce a circumferential current. If you look at the current
flowing from the earth to each radial wire, you'll see that the sum of
these currents will be purely radial, assuming that the system is
symmetrical, i.e., radials are equally spaced and equal length, the
ground is homogeneous, and the radiator is vertical. Consider a bit of
current returning between two radials, which is a little closer to the
radial on the right. It'll detour to the right, giving it a rightward
component as well as an inward radial component. But for every such bit
of current, there's another one the same distance from the radial to the
left which will have leftward and inward radial components. The radial
components are in the same direction (inward) so will add but the
circumferential ones (leftward and rightward) cancel, leaving a net
radial current flow. You can say that the returning currents bend to the
right or left as they propagate toward the antenna base, but not that
there's a systematic circumferential current flow -- no current crosses
from radial to radial in a clockwise or counterclockwise circular
pattern like Richard implied.

I recall reading a paper which showed that connecting radials with
circumferential wires actually degrades a ground system's effectiveness,
but I wasn't able to lay my hand on it when I looked.

Roy Lewallen, W7EL


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Old April 13th 07, 12:31 AM posted to rec.radio.amateur.antenna
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On Thu, 12 Apr 2007 13:53:30 -0700, Roy Lewallen
wrote:

no current crosses
from radial to radial in a clockwise or counterclockwise circular
pattern like Richard implied.


Hi Roy,

This, like:
Your answers to the two questions I asked are
that you don't know and you don't know.

inject your meaning into this dialog as though I wrote it.

I wrote neither that I didn't know (this is strictly your
interpretation) nor have I implied radial to radial conduction.

Please review the correspondence and respond directly to my comments
as written instead of creating my talking points for me. This is
Cecil's style, not yours.

73's
Richard Clark, KB7QHC
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