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Dave, here is the model I sent you before, a 5/8 wave radiator and 4 x 23' foot slanted down radials. In order to show you why I think this model might have flaws in the results, ie. trying to respond like two stacked 5/8 waves as collinear which the results seem to indicate.

I had a thought that this design would mostly be radiating from the radials and the radiator would only be helping a little by acting like a load rather than a radiating radiator.

So, I took the model and removed most of the radiator making it 4.8" inches long rather than 22.5' feet long, see wire #1 in the second model below. I wanted to see if the gain would still show up on this butchered up antenna...and it does as you will note here:

[ATTACH]10632[/ATTACH]

The increase in gain noted by this model with the short radiator is probably mostly due to a substantial increase in the SWR, from about 13.0:1 for the original model to over 100:1 SWR for the shorter model. The pattern for the shorter model has changed for the worse, but the gain is still indicating a big gain...like we might expect with two vertically stacked collinear 5/8 wave radiators.

Just be aware that your test idea may not respond like the model is suggesting.

<blockquote data-quote="Marconi" data-source="post: 435132" data-attributes="member: 903">Dave, here is the model I sent you before, a 5/8 wave radiator and 4 x 23&#039; foot slanted down radials. In order to show you why I think this model might have flaws in the results, ie. trying to respond like two stacked 5/8 waves as collinear which the results seem to indicate.&nbsp;I had a thought that this design would mostly be radiating from the radials and the radiator would only be helping a little by acting like a load rather than a radiating radiator.&nbsp;So, I took the model and removed most of the radiator making it 4.8&quot; inches long rather than 22.5&#039; feet long, see wire #1 in the second model below. I wanted to see if the gain would still show up on this butchered up antenna...and it does as you will note here:&nbsp;[ATTACH]10632[/ATTACH]&nbsp;The increase in gain noted by this model with the short radiator is probably mostly due to a substantial increase in the SWR, from about 13.0:1 for the original model to over 100:1 SWR for the shorter model. The pattern for the shorter model has changed for the worse, but the gain is still indicating a big gain...like we might expect with two vertically stacked collinear 5/8 wave radiators.&nbsp;Just be aware that your test idea may not respond like the model is suggesting.</blockquote>

[QUOTE="Marconi, post: 435132, member: 903"] Dave, here is the model I sent you before, a 5/8 wave radiator and 4 x 23' foot slanted down radials. In order to show you why I think this model might have flaws in the results, ie. trying to respond like two stacked 5/8 waves as collinear which the results seem to indicate. I had a thought that this design would mostly be radiating from the radials and the radiator would only be helping a little by acting like a load rather than a radiating radiator. So, I took the model and removed most of the radiator making it 4.8" inches long rather than 22.5' feet long, see wire #1 in the second model below. I wanted to see if the gain would still show up on this butchered up antenna...and it does as you will note here: [ATTACH]10632.vB[/ATTACH] The increase in gain noted by this model with the short radiator is probably mostly due to a substantial increase in the SWR, from about 13.0:1 for the original model to over 100:1 SWR for the shorter model. The pattern for the shorter model has changed for the worse, but the gain is still indicating a big gain...like we might expect with two vertically stacked collinear 5/8 wave radiators. Just be aware that your test idea may not respond like the model is suggesting. [/QUOTE]

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