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I'm saying that what works in EZNEC on this experiment is off by 100% when compared to the phase shift required in the field. You' collinear model shows what is expected anytime we add these four wires to a 1/2 wave ground plane.

If you can add a 180 degree phase shift and 1/2 wave element to the Sigma and show gain in EZNEC, this proves beyond a doubt that EZNEC interprets the Sigma as a 1/2 wave radiator with NO significant in phase radiation from the cone.

The fact that we have to reduce the phase shift in half to make the antenna have gain in the field shows there is significant in phase radiation from the cone that cannot be ignored by using the 180 degree phase shift that EZNEC suggests.

The fact the antenna in the field has virtually no change in gain from the stock version when used with a 180 degree shift shows the radiation from the cone is comparable to an open 1/4 wave radiator.

I base this on the fact that it takes 1/4 wave of the added top 1/2 wave to cancel the productive radiation from the cone while the second 1/4 wave of the added 1/2 wave merely returns the antenna to its original gain when used with a 180 degree phase shift.

<blockquote data-quote="Shockwave" data-source="post: 445502" data-attributes="member: 10882">I&#039;m saying that what works in EZNEC on this experiment is off by 100% when compared to the phase shift required in the field. You&#039; collinear model shows what is expected anytime we add these four wires to a 1/2 wave ground plane. If you can add a 180 degree phase shift and 1/2 wave element to the Sigma and show gain in EZNEC, this proves beyond a doubt that EZNEC interprets the Sigma as a 1/2 wave radiator with NO significant in phase radiation from the cone.The fact that we have to reduce the phase shift in half to make the antenna have gain in the field shows there is significant in phase radiation from the cone that cannot be ignored by using the 180 degree phase shift that EZNEC suggests. The fact the antenna in the field has virtually no change in gain from the stock version when used with a 180 degree shift shows the radiation from the cone is comparable to an open 1/4 wave radiator. I base this on the fact that it takes 1/4 wave of the added top 1/2 wave to cancel the productive radiation from the cone while the second 1/4 wave of the added 1/2 wave merely returns the antenna to its original gain when used with a 180 degree phase shift.</blockquote>

[QUOTE="Shockwave, post: 445502, member: 10882"] I'm saying that what works in EZNEC on this experiment is off by 100% when compared to the phase shift required in the field. You' collinear model shows what is expected anytime we add these four wires to a 1/2 wave ground plane. If you can add a 180 degree phase shift and 1/2 wave element to the Sigma and show gain in EZNEC, this proves beyond a doubt that EZNEC interprets the Sigma as a 1/2 wave radiator with NO significant in phase radiation from the cone. The fact that we have to reduce the phase shift in half to make the antenna have gain in the field shows there is significant in phase radiation from the cone that cannot be ignored by using the 180 degree phase shift that EZNEC suggests. The fact the antenna in the field has virtually no change in gain from the stock version when used with a 180 degree shift shows the radiation from the cone is comparable to an open 1/4 wave radiator. I base this on the fact that it takes 1/4 wave of the added top 1/2 wave to cancel the productive radiation from the cone while the second 1/4 wave of the added 1/2 wave merely returns the antenna to its original gain when used with a 180 degree phase shift. [/QUOTE]

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