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Homer, I was going by what you posted on the other forum.

All, I'm suggesting is that the small difference in capture area among all of the CB antennas we might talk about here are probably insignificant to our experience working our radios.

The way I read it, you're suggesting that the capture area of a 1/4 vs. 1/2, vs. .625, vs. .64 is what accounts for the progressive differences in gain...and I just disagree.

We all pretty much understand that antennas at different locations will likely produce different results.

IMO my models over real Earth tend to follow the trends toward more gain and better angles for the longer radiators just as noted in the list above, but I attribute that to Mother Earth, the fact that the current maximums for the longer antennas are higher, and more importantly to how symmetrical the radiator is relative to its other elements in design.

I don't think capture area has a thing to do with why we see more gain and better angles among this group.

Here is the model that I used. I started with a 1/4 wave ground plane with 4 x 108" radials below a 108" radiator. I did not tune or tweak these models I just got the dimensions as close as I could. I used the typical math idea to determine the wavelength for each model. Then I turned the antenna over on is side at 36' feet high in order to make all the antennas at the same exact height. I added an overlay for each antenna for easy comparison of the differences Eznec predicts.

Note in the overlay that the black and green patterns follow the same exact path.

[ATTACH]8098[/ATTACH]

<blockquote data-quote="Marconi" data-source="post: 384185" data-attributes="member: 903">Homer, I was going by what you posted on the other forum. &nbsp;&nbsp;All, I&#039;m suggesting is that the small difference in capture area among all of the CB antennas we might talk about here are probably insignificant to our experience working our radios. &nbsp;The way I read it, you&#039;re suggesting that the capture area of a 1/4 vs. 1/2, vs. .625, vs. .64 is what accounts for the progressive differences in gain...and I just disagree.&nbsp;We all pretty much understand that antennas at different locations will likely produce different results. &nbsp;IMO my models over real Earth tend to follow the trends toward more gain and better angles for the longer radiators just as noted in the list above, but I attribute that to Mother Earth, the fact that the current maximums for the longer antennas are higher, and more importantly to how symmetrical the radiator is relative to its other elements in design. &nbsp;I don&#039;t think capture area has a thing to do with why we see more gain and better angles among this group.&nbsp;Here is the model that I used. I started with a 1/4 wave ground plane with 4 x 108&quot; radials below a 108&quot; radiator. I did not tune or tweak these models I just got the dimensions as close as I could. I used the typical math idea to determine the wavelength for each model. Then I turned the antenna over on is side at 36&#039; feet high in order to make all the antennas at the same exact height. I added an overlay for each antenna for easy comparison of the differences Eznec predicts.&nbsp;Note in the overlay that the black and green patterns follow the same exact path.&nbsp;[ATTACH]8098[/ATTACH]</blockquote>

[QUOTE="Marconi, post: 384185, member: 903"] Homer, I was going by what you posted on the other forum. All, I'm suggesting is that the small difference in capture area among all of the CB antennas we might talk about here are probably insignificant to our experience working our radios. The way I read it, you're suggesting that the capture area of a 1/4 vs. 1/2, vs. .625, vs. .64 is what accounts for the progressive differences in gain...[B][I]and I just disagree.[/I][/B] We all pretty much understand that antennas at different locations will likely produce different results. IMO my models over real Earth tend to follow the trends toward more gain and better angles for the longer radiators just as noted in the list above, but I attribute that to Mother Earth, the fact that the current maximums for the longer antennas are higher, and more importantly to how symmetrical the radiator is relative to its other elements in design. I don't think capture area has a thing to do with why we see more gain and better angles among this group. Here is the model that I used. I started with a 1/4 wave ground plane with 4 x 108" radials below a 108" radiator. I did not tune or tweak these models I just got the dimensions as close as I could. I used the typical math idea to determine the wavelength for each model. Then I turned the antenna over on is side at 36' feet high in order to make all the antennas at the same exact height. I added an overlay for each antenna for easy comparison of the differences Eznec predicts. Note in the overlay that the black and green patterns follow the same exact path. [ATTACH]8098.vB[/ATTACH] [/QUOTE]

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