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I've noticed discrepancies between the two programs when working with this design for some time now and they just add to the confusion. I've done several experiments that lead me to strongly believe EZNEC mistakes this design as a coaxial end fed 1/2 wave.

I base this on the fact if you try to improve the design in ways that require the program to understand the correct radiation phase angles, the attempt fails every time in the field. Treat the design as a 1/2 wave over a 1/4 wave and some success can be found.

When I compare what's going on with the cone in both programs, I don't see the exact opposite placement of currents. To me it looks as though the radiation currents on the cone are concentrated more towards the middle of the structure in CST. That confuses me even more while both programs report the same current distribution along the main vertical radiator.

PS: The current on the main radiator is identical in both programs as far as I can tell. EZNEC shows the main radiator starting off at maximum current. It reaches minimum current 1/4 wavelength up, right around the loop. Then begins another 1/2 wave cycle where it starts off with minimum current, reaches a peak another 1/4 wave up and diminishes to no current at the top. I cropped the picture because it was too large to post.

<blockquote data-quote="Shockwave" data-source="post: 385163" data-attributes="member: 10882">I&#039;ve noticed discrepancies between the two programs when working with this design for some time now and they just add to the confusion. I&#039;ve done several experiments that lead me to strongly believe EZNEC mistakes this design as a coaxial end fed 1/2 wave.I base this on the fact if you try to improve the design in ways that require the program to understand the correct radiation phase angles, the attempt fails every time in the field. Treat the design as a 1/2 wave over a 1/4 wave and some success can be found.When I compare what&#039;s going on with the cone in both programs, I don&#039;t see the exact opposite placement of currents. To me it looks as though the radiation currents on the cone are concentrated more towards the middle of the structure in CST. That confuses me even more while both programs report the same current distribution along the main vertical radiator.PS: The current on the main radiator is identical in both programs as far as I can tell. EZNEC shows the main radiator starting off at maximum current. It reaches minimum current 1/4 wavelength up, right around the loop. Then begins another 1/2 wave cycle where it starts off with minimum current, reaches a peak another 1/4 wave up and diminishes to no current at the top. I cropped the picture because it was too large to post.</blockquote>

[QUOTE="Shockwave, post: 385163, member: 10882"] I've noticed discrepancies between the two programs when working with this design for some time now and they just add to the confusion. I've done several experiments that lead me to strongly believe EZNEC mistakes this design as a coaxial end fed 1/2 wave. I base this on the fact if you try to improve the design in ways that require the program to understand the correct radiation phase angles, the attempt fails every time in the field. Treat the design as a 1/2 wave over a 1/4 wave and some success can be found. When I compare what's going on with the cone in both programs, I don't see the exact opposite placement of currents. To me it looks as though the radiation currents on the cone are concentrated more towards the middle of the structure in CST. That confuses me even more while both programs report the same current distribution along the main vertical radiator. PS: The current on the main radiator is identical in both programs as far as I can tell. EZNEC shows the main radiator starting off at maximum current. It reaches minimum current 1/4 wavelength up, right around the loop. Then begins another 1/2 wave cycle where it starts off with minimum current, reaches a peak another 1/4 wave up and diminishes to no current at the top. I cropped the picture because it was too large to post. [/QUOTE]

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