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BM here is a 5 element horizontal yagi that was a file attached to the Eznec 5 software. I modified it with a mast and added a simulated A99 with 4 horizontal radials sitting above the beam.

Note that there is a difference in the patterns, but it is negligible even though the antennas are close. I doubt anyone could notice the change in operations just as noted in these patterns.

There is a suggestion here that opposite polarity makes a powerful difference in antenna response, and in this case the A99 with radials above the beam is almost invisible.

Sorry I did not model all the options you note.

The radials are 1/4 wave and the A99 is about 6' feet above the beam. The beam is approximately 20' feet long and the only alteration I made to the beam was to add an insulated boom and a mast attached to the Earth. I did compare the beam's pattern between the boom and no boom and they were also very similar in gain and angle.

[ATTACH]5115[/ATTACH]

Here is the A99 pattern. It was somewhat ill affected by being above the beam, but it might not be much. I also include the wires view of this antenna setup.

[ATTACH]5116[/ATTACH]

<blockquote data-quote="Marconi" data-source="post: 299254" data-attributes="member: 903">BM here is a 5 element horizontal yagi that was a file attached to the Eznec 5 software. I modified it with a mast and added a simulated A99 with 4 horizontal radials sitting above the beam.&nbsp;Note that there is a difference in the patterns, but it is negligible even though the antennas are close. I doubt anyone could notice the change in operations just as noted in these patterns.&nbsp;There is a suggestion here that opposite polarity makes a powerful difference in antenna response, and in this case the A99 with radials above the beam is almost invisible. &nbsp;Sorry I did not model all the options you note.&nbsp;The radials are 1/4 wave and the A99 is about 6&#039; feet above the beam. The beam is approximately 20&#039; feet long and the only alteration I made to the beam was to add an insulated boom and a mast attached to the Earth. I did compare the beam&#039;s pattern between the boom and no boom and they were also very similar in gain and angle.&nbsp;[ATTACH]5115[/ATTACH]&nbsp;Here is the A99 pattern. It was somewhat ill affected by being above the beam, but it might not be much. I also include the wires view of this antenna setup.&nbsp;[ATTACH]5116[/ATTACH]</blockquote>

[QUOTE="Marconi, post: 299254, member: 903"] BM here is a 5 element horizontal yagi that was a file attached to the Eznec 5 software. I modified it with a mast and added a simulated A99 with 4 horizontal radials sitting above the beam. Note that there is a difference in the patterns, but it is negligible even though the antennas are close. I doubt anyone could notice the change in operations just as noted in these patterns. There is a suggestion here that opposite polarity makes a powerful difference in antenna response, and in this case the A99 with radials above the beam is almost invisible. Sorry I did not model all the options you note. The radials are 1/4 wave and the A99 is about 6' feet above the beam. The beam is approximately 20' feet long and the only alteration I made to the beam was to add an insulated boom and a mast attached to the Earth. I did compare the beam's pattern between the boom and no boom and they were also very similar in gain and angle. [ATTACH]5115.vB[/ATTACH] Here is the A99 pattern. It was somewhat ill affected by being above the beam, but it might not be much. I also include the wires view of this antenna setup. [ATTACH]5116.vB[/ATTACH] [/QUOTE]

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