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I'm claiming nothing. I'm just reporting what both EZNEC and CST have uncovered with respect to currents on the cone because some are still struggling to understand the models. Even EZNEC displays this current distribution on the cone.

The pink current line is bowed away from the base of the 4 radials the most and comes back to nearly zero current along the loop. Common sense tells us the base of the radials carry the current node and the loop is the voltage node.

The only simultaneous inverted current anywhere on this antenna takes place along the first 1/4 wave of the main vertical radiator as displayed in CST. Because it's inverted, this radiation current is undesirable and is exactly why it is prevented from radiating by the cone around it. Of course all of these currents are reversing their phase 27 million times per second and that's why RF radiates and DC does not.

Having said that, I admit there are still certain aspects dealing with antennas and phase inversion that I fail to fully understand. For example my Yagi driven element is currently using a T-Match. Both sides of this balanced element are driven. The interesting part is that they must be driven 180 degrees out of phase from one another.

This clearly demonstrates that one side of the balanced element is completely out of phase from the other. Can anyone explain why equal but opposite radiation currents do not cancel each other in the far field? With these things in mind, I also admit I'm having a hard time finding anything that resembles this phase inversion in the Sigma design.

<blockquote data-quote="Shockwave" data-source="post: 385139" data-attributes="member: 10882">I&#039;m claiming nothing. I&#039;m just reporting what both EZNEC and CST have uncovered with respect to currents on the cone because some are still struggling to understand the models. Even EZNEC displays this current distribution on the cone.The pink current line is bowed away from the base of the 4 radials the most and comes back to nearly zero current along the loop. Common sense tells us the base of the radials carry the current node and the loop is the voltage node.The only simultaneous inverted current anywhere on this antenna takes place along the first 1/4 wave of the main vertical radiator as displayed in CST. Because it&#039;s inverted, this radiation current is undesirable and is exactly why it is prevented from radiating by the cone around it. Of course all of these currents are reversing their phase 27 million times per second and that&#039;s why RF radiates and DC does not.Having said that, I admit there are still certain aspects dealing with antennas and phase inversion that I fail to fully understand. For example my Yagi driven element is currently using a T-Match. Both sides of this balanced element are driven. The interesting part is that they must be driven 180 degrees out of phase from one another.This clearly demonstrates that one side of the balanced element is completely out of phase from the other. Can anyone explain why equal but opposite radiation currents do not cancel each other in the far field? With these things in mind, I also admit I&#039;m having a hard time finding anything that resembles this phase inversion in the Sigma design.</blockquote>

[QUOTE="Shockwave, post: 385139, member: 10882"] I'm claiming nothing. I'm just reporting what both EZNEC and CST have uncovered with respect to currents on the cone because some are still struggling to understand the models. Even EZNEC displays this current distribution on the cone. The pink current line is bowed away from the base of the 4 radials the most and comes back to nearly zero current along the loop. Common sense tells us the base of the radials carry the current node and the loop is the voltage node. The only simultaneous inverted current anywhere on this antenna takes place along the first 1/4 wave of the main vertical radiator as displayed in CST. Because it's inverted, this radiation current is undesirable and is exactly why it is prevented from radiating by the cone around it. Of course all of these currents are reversing their phase 27 million times per second and that's why RF radiates and DC does not. Having said that, I admit there are still certain aspects dealing with antennas and phase inversion that I fail to fully understand. For example my Yagi driven element is currently using a T-Match. Both sides of this balanced element are driven. The interesting part is that they must be driven 180 degrees out of phase from one another. This clearly demonstrates that one side of the balanced element is completely out of phase from the other. Can anyone explain why equal but opposite radiation currents do not cancel each other in the far field? With these things in mind, I also admit I'm having a hard time finding anything that resembles this phase inversion in the Sigma design. [/QUOTE]

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