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Hey Marconi, I was hoping you or Bob85 would chime in on my models at some point. I know you two, as well as a few others, have done far more work than I on this antenna in the past. I am the latecomer to this show.

AGT was in line, actually dead on with a 1. I used a trick that ghz24 showed me to achieve that. The higher than normal gains were because I mounted the antenna very high. I did this because I was playing with a feature I knew about in 4Nec2 that I hadn't played with before. Essentially I can change the length of a wire through a range of lengths, and can map the results of said changes, like SWR gain and impedance, on a graph. What I was doing was graphing the changes in the mast length, and the upper edge of those lengths was about two wavelength high, which means I needed to have the feed point of the antenna at least that high. When I lowered the antenna back down for the comparison to the I-10k antenna the gain numbers should be more in line with what you expect.

Here is an example of one of those graphs (their are a few posted above).

Here the SWR range is on the left, and the length of the mast in inches is across the bottom. With this I can effectively map out the results of making various changes to an antenna.

When it comes to feed points, we definitely have different ideas and different methods. We have had that discussion in the past.

The DB

<blockquote data-quote="The DB" data-source="post: 590959" data-attributes="member: 21346">Hey Marconi, I was hoping you or Bob85 would chime in on my models at some point.&nbsp; I know you two, as well as a few others, have done far more work than I on this antenna in the past.&nbsp; I am the latecomer to this show.AGT was in line, actually dead on with a 1.&nbsp; I used a trick that ghz24 showed me to achieve that.&nbsp; The higher than normal gains were because I mounted the antenna very high.&nbsp; I did this because I was playing with a feature I knew about in 4Nec2 that I hadn&#039;t played with before.&nbsp; Essentially I can change the length of a wire through a range of lengths, and can map the results of said changes, like SWR gain and impedance, on a graph.&nbsp; What I was doing was graphing the changes in the mast length, and the upper edge of those lengths was about two wavelength high, which means I needed to have the feed point of the antenna at least that high.&nbsp; When I lowered the antenna back down for the comparison to the I-10k antenna the gain numbers should be more in line with what you expect.Here is an example of one of those graphs (their are a few posted above).<img src="http://hittman.us/pictures/6-10-17/aprdswr.jpg" alt="" class="fr-fic fr-dii fr-draggable " data-size="" style="" />Here the SWR range is on the left, and the length of the mast in inches is across the bottom.&nbsp; With this I can effectively map out the results of making various changes to an antenna.When it comes to feed points, we definitely have different ideas and different methods.&nbsp; We have had that discussion in the past.<a href="http://hittman.us" target="_blank">The DB</a></blockquote>

[QUOTE="The DB, post: 590959, member: 21346"] Hey Marconi, I was hoping you or Bob85 would chime in on my models at some point. I know you two, as well as a few others, have done far more work than I on this antenna in the past. I am the latecomer to this show. AGT was in line, actually dead on with a 1. I used a trick that ghz24 showed me to achieve that. The higher than normal gains were because I mounted the antenna very high. I did this because I was playing with a feature I knew about in 4Nec2 that I hadn't played with before. Essentially I can change the length of a wire through a range of lengths, and can map the results of said changes, like SWR gain and impedance, on a graph. What I was doing was graphing the changes in the mast length, and the upper edge of those lengths was about two wavelength high, which means I needed to have the feed point of the antenna at least that high. When I lowered the antenna back down for the comparison to the I-10k antenna the gain numbers should be more in line with what you expect. Here is an example of one of those graphs (their are a few posted above). [IMG]http://hittman.us/pictures/6-10-17/aprdswr.jpg[/IMG] Here the SWR range is on the left, and the length of the mast in inches is across the bottom. With this I can effectively map out the results of making various changes to an antenna. When it comes to feed points, we definitely have different ideas and different methods. We have had that discussion in the past. [URL='http://hittman.us'][COLOR=#000000]The DB[/COLOR][/URL] [/QUOTE]

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