I though everybody knew this.
BTW, I heartily recommend AutoEZ as adjunct to EZNEC. Dan's site (AC6LA.com) is
a treasure trove even if you don't buy the program.
For example of a feature: "With AutoEZ you have a second choice for the method
of segmentation. You can specify a physical length for each segment. This second
method may be useful in cases where it is important to keep the segment
junctions aligned between closely-spaced wires"
Wes N7WS
On 1/9/2021 1:07 PM, Richard (Rick) Karlquist wrote:
Excellent navigation! I found it easily. I will quote the relevant
text from it below:
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Closely Spaced Wires
When modeling parallel or nearly parallel wires which are closely spaced, it
can be very important to align the segment junctions. That is, they should be
directly across from each other. This is particularly true if the segment
length is greater than the wire spacing. As the segment length gets shorter
compared to the wire spacing, this requirement becomes less important. When
segment junctions are misaligned but need to be aligned, results can change
dramatically as segmentation is changed.
The easiest way to assure that aligned parallel wires have aligned segment
junctions is to give the wires identical lengths and numbers of segments. If
the wires are staggered or different lengths, break them into more wires. Make
the portions of the wires which are directly across from each other into
separate wires of equal length and number of segments. An example of this
technique is shown below, where the long wire of a J-pole antenna was broken
into two wires. Wire 4 is made the same length and given the same number of
segments as parallel wire 6. The upper wire is segmented to make its segment
length approximately equal to the segment length on wire 4. (This is a close
up view – some of the long wire, and its number, aren't shown.)
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So I was indeed clueless, but no more. Basically, all I need to do
is align the segments; who knew? Certainly isn't obvious. Now I get it.
Very clear writing by Roy, as usual. The J-pole example is
perfect.
73
Rick N6RK
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