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With all due respect I beg to disagree.

I skimmed through the entire chapter on grounding of the 23'rd edition of the ARRL Antenna Book before posting that post, and I specifically read it before posting this one. The charts of radial length and efficiency (performance) are all for antennas mounted on or near the earth. When they start talking about elevated radial systems, all of that goes away. Said book also talks about elevated antennas only needing 4 1/4 wavelength radials to be as efficient as a large number of radials on a ground mounted antenna.

Typically I agree with most of what you talk about, I find it odd that we would disagree with what is written in the same highly reliable source. I am curious as to what would bring about this difference in perspective.

I understand exactly what you were saying. You were talking about efficiency, I was taking that and factoring in the change in feed point impedance that you will also see when making this change on an elevated antenna, and concluded that the change you would make to account for efficiency will not be enough to account for the change in feed point impedance. To take that a step further, depending on the matching system that antennas uses, adjusting said matching circuit may also not be enough to account for said change.

The DB

<blockquote data-quote="The DB" data-source="post: 727670" data-attributes="member: 21346">With all due respect I beg to disagree.I skimmed through the entire chapter on grounding of the 23&#039;rd edition of the ARRL Antenna Book before posting that post, and I specifically read it before posting this one.&nbsp; The charts of radial length and efficiency (performance) are all for antennas mounted on or near the earth.&nbsp; When they start talking about elevated radial systems, all of that goes away.&nbsp; Said book also talks about elevated antennas only needing 4 1/4 wavelength radials to be as efficient as a large number of radials on a ground mounted antenna.Typically I agree with most of what you talk about, I find it odd that we would disagree with what is written in the same highly reliable source.&nbsp; I am curious as to what would bring about this difference in perspective.I understand exactly what you were saying.&nbsp;&nbsp; You were talking about efficiency, I was taking that and factoring in the change in feed point impedance that you will also see when making this change on an elevated antenna, and concluded that the change you would make to account for efficiency will not be enough to account for the change in feed point impedance.&nbsp; To take that a step further, depending on the matching system that antennas uses, adjusting said matching circuit may also not be enough to account for said change.The DB</blockquote>

[QUOTE="The DB, post: 727670, member: 21346"] With all due respect I beg to disagree. I skimmed through the entire chapter on grounding of the 23'rd edition of the ARRL Antenna Book before posting that post, and I specifically read it before posting this one. The charts of radial length and efficiency (performance) are all for antennas mounted on or near the earth. When they start talking about elevated radial systems, all of that goes away. Said book also talks about elevated antennas only needing 4 1/4 wavelength radials to be as efficient as a large number of radials on a ground mounted antenna. Typically I agree with most of what you talk about, I find it odd that we would disagree with what is written in the same highly reliable source. I am curious as to what would bring about this difference in perspective. I understand exactly what you were saying. You were talking about efficiency, I was taking that and factoring in the change in feed point impedance that you will also see when making this change on an elevated antenna, and concluded that the change you would make to account for efficiency will not be enough to account for the change in feed point impedance. To take that a step further, depending on the matching system that antennas uses, adjusting said matching circuit may also not be enough to account for said change. The DB [/QUOTE]

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