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[ATTACH=full]59733[/ATTACH]

That radiation pattern reminds me of some of the vector models from back in the day. Its not exact, but I recall some of my models having little to no high angle radiation, and most of said radiation was in a low angle lobe. And it wasn't every model, just some of them.

The shown current/phase distribution confuses me. It is very unexpected, at least compared to how I would design/build such an antenna. Many questions appear in my head about this part alone, although I want to put some more thought into it first. I do find it highly unusual that the lower 1/4 wavelength section isn't completely in phase with itself, and carries the same amount of out of phase currents as the 5/8 wavelength element above? For a collinear design this is at best highly unusual. I would also ask, at first glance, are the radials shorter than the vertical 1/4 wavelength element? I wonder if these two things factor in to create some form of matching?

I wish I had more time to play with modeling at the moment.

I'm not seeing them listed here, but did we ever get the dimensions of this antenna? The inductance of that phasing coil would also help.

The DB

<blockquote data-quote="The DB" data-source="post: 793960" data-attributes="member: 21346">[ATTACH=full]59733[/ATTACH]That radiation pattern reminds me of some of the vector models from back in the day.&nbsp; Its not exact, but I recall some of my models having little to no high angle radiation, and most of said radiation was in a low angle lobe.&nbsp; And it wasn&#039;t every model, just some of them.The shown current/phase distribution confuses me.&nbsp; It is very unexpected, at least compared to how I would design/build such an antenna.&nbsp; Many questions appear in my head about this part alone, although I want to put some more thought into it first.&nbsp; I do find it highly unusual that the lower 1/4 wavelength section isn&#039;t completely in phase with itself, and carries the same amount of out of phase currents as the 5/8 wavelength element above?&nbsp; For a collinear design this is at best highly unusual.&nbsp; I would also ask, at first glance, are the radials shorter than the vertical 1/4 wavelength element?&nbsp; I wonder if these two things factor in to create some form of matching?I wish I had more time to play with modeling at the moment.I&#039;m not seeing them listed here, but did we ever get the dimensions of this antenna?&nbsp; The inductance of that phasing coil would also help.&nbsp; The DB</blockquote>

[QUOTE="The DB, post: 793960, member: 21346"] [ATTACH type="full"]59733[/ATTACH] That radiation pattern reminds me of some of the vector models from back in the day. Its not exact, but I recall some of my models having little to no high angle radiation, and most of said radiation was in a low angle lobe. And it wasn't every model, just some of them. The shown current/phase distribution confuses me. It is very unexpected, at least compared to how I would design/build such an antenna. Many questions appear in my head about this part alone, although I want to put some more thought into it first. I do find it highly unusual that the lower 1/4 wavelength section isn't completely in phase with itself, and carries the same amount of out of phase currents as the 5/8 wavelength element above? For a collinear design this is at best highly unusual. I would also ask, at first glance, are the radials shorter than the vertical 1/4 wavelength element? I wonder if these two things factor in to create some form of matching? I wish I had more time to play with modeling at the moment. I'm not seeing them listed here, but did we ever get the dimensions of this antenna? The inductance of that phasing coil would also help. The DB [/QUOTE]

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