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One of us only knows CMC does not exist when it conveniently fits into his thoughtless babble. On the other hand when it's convenient to mislead people into thinking the "CMC destroys the pattern as soon as the mast and coax are added", he'll quote W8JI saying just that.

He can't have it both ways and it's not realistic to think this end fed antenna would not have any CMC. What is not apparent until you field test the phase of this radiator is the CMC radiates constructively on the cone as a second current that is shifted by 90 degrees. That's what is causing the unusual pattern CST displays.

I think I've already done what you say here DB in an attempt to confirm the incorrect assumptions W8JI has made in the past about this design. He says adding 4 horizontal radials from the base will improve performance due to CMC.

I did what W8JI said and the gain went down adding 4 horizontal 1/4 wave radials at the base of the cone. As I recall there may have been a very minor change in impedance but nothing to complain about other than the small drop in gain.

I then began to sweep these new radials upwards and toward the cone. When they were close to the cone, the gain returned and the small change in impedance disappeared. I believe this proved there are constructive CMC on the cone and the reduction in gain was due to drawing desired currents off the cone by placing them on the horizontal radials where they do not benefit to this design.

<blockquote data-quote="Shockwave" data-source="post: 498255" data-attributes="member: 10882">One of us only knows CMC does not exist when it conveniently fits into his thoughtless babble. On the other hand when it&#039;s convenient to mislead people into thinking the &quot;CMC destroys the pattern as soon as the mast and coax are added&quot;, he&#039;ll quote W8JI saying just that.&nbsp;He can&#039;t have it both ways and it&#039;s not realistic to think this end fed antenna would not have any CMC. What is not apparent until you field test the phase of this radiator is the CMC radiates constructively on the cone as a second current that is shifted by 90 degrees. That&#039;s what is causing the unusual pattern CST displays.&nbsp;&nbsp;&nbsp;I think I&#039;ve already done what you say here DB in an attempt to confirm the incorrect assumptions W8JI has made in the past about this design. He says adding 4 horizontal radials from the base will improve performance due to CMC.&nbsp;I did what W8JI said and the gain went down adding 4 horizontal 1/4 wave radials at the base of the cone. As I recall there may have been a very minor change in impedance but nothing to complain about other than the small drop in gain.&nbsp;I then began to sweep these new radials upwards and toward the cone. When they were close to the cone, the gain returned and the small change in impedance disappeared. I believe this proved there are constructive CMC on the cone and the reduction in gain was due to drawing desired currents off the cone by placing them on the horizontal radials where they do not benefit to this design.</blockquote>

[QUOTE="Shockwave, post: 498255, member: 10882"] One of us only knows CMC does not exist when it conveniently fits into his thoughtless babble. On the other hand when it's convenient to mislead people into thinking the "CMC destroys the pattern as soon as the mast and coax are added", he'll quote W8JI saying just that. He can't have it both ways and it's not realistic to think this end fed antenna would not have any CMC. What is not apparent until you field test the phase of this radiator is the CMC radiates constructively on the cone as a second current that is shifted by 90 degrees. That's what is causing the unusual pattern CST displays. I think I've already done what you say here DB in an attempt to confirm the incorrect assumptions W8JI has made in the past about this design. He says adding 4 horizontal radials from the base will improve performance due to CMC. I did what W8JI said and the gain went down adding 4 horizontal 1/4 wave radials at the base of the cone. As I recall there may have been a very minor change in impedance but nothing to complain about other than the small drop in gain. I then began to sweep these new radials upwards and toward the cone. When they were close to the cone, the gain returned and the small change in impedance disappeared. I believe this proved there are constructive CMC on the cone and the reduction in gain was due to drawing desired currents off the cone by placing them on the horizontal radials where they do not benefit to this design. [/QUOTE]

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