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I'm not, mainly because of the results I got with my first attempt at modeling my vehicle.

I'm getting an AGT of 0.96, I think the larger number of elements are actually helping here.

That 36 ohm number, there are exactly three cases that that is relevant.
If you are mounted over a perfect ground, (that is a 1/4 wavelength antenna with the other half being the perfect ground, not a ground plane antenna mounted some distance above perfect ground) good luck with that irl.
If you are over an analog of a perfect ground, such as, say, 120 ground plane radials of 1/4 wavelength. That would be an 18 foot diameter ground plane, good luck fitting that on a car.
The things that affect the antennas feed point impedance just happen to balance each other out and give that as a result, but how do you know that happened?
Regarding number 3, impedance is a funny thing, there are things that will lower it, such as not enough metal underneath the antenna, you know, like on all vehicles that are road legal, and things that will raise it, like how close the antenna is to the imperfect earth below the antenna system. In a vehicle those both play their parts and modify the feed point impedance, as well as the antenna's radiation resistance. I agree that the number most people shoot for, namely 50 ohms, isn't really what they think it is, but at the same time, 36 ohms isn't necessarily the number to shoot for either.

Those are also not the only things that affect impedance, as well as the antenna's radiation resistance.

Not having the models myself it is hard to say, but the model with more wires seems to be less efficient and more directional, at least as far as the models you posted are concerned. The maximum gain figure isn't all you need to be looking at, but the entire pattern, and in the case of these models the side gain as well, which is listed and noticeably different. The patterns don't look anything alike, so aside from the gain numbers appearing to be about the same, I would definitely not call them similar.

As I stated above, 0.96 AGT, and that was just how it ended up, I didn't have to modify the model in any way. Actually modifying various aspects of the model didn't actually change the AGT, so it seems pretty stable, more so than other models I have made in the past.

The DB

<blockquote data-quote="The DB" data-source="post: 578832" data-attributes="member: 21346">I&#039;m not, mainly because of the results I got with my first attempt at modeling my vehicle.I&#039;m getting an AGT of 0.96, I think the larger number of elements are actually helping here.That 36 ohm number, there are exactly three cases that that is relevant.<ol>
<li data-xf-list-type="ol">If you are mounted over a perfect ground, (that is a 1/4 wavelength antenna with the other half being the perfect ground, not a ground plane antenna mounted some distance above perfect ground) good luck with that irl.</li>
<li data-xf-list-type="ol">If you are over an analog of a perfect ground, such as, say, 120 ground plane radials of 1/4 wavelength.&nbsp; That would be an 18 foot diameter ground plane, good luck fitting that on a car.</li>
<li data-xf-list-type="ol">The things that affect the antennas feed point impedance just happen to balance each other out and give that as a result, but how do you know that happened?</li>
</ol>Regarding number 3, impedance is a funny thing, there are things that will lower it, such as not enough metal underneath the antenna, you know, like on all vehicles that are road legal, and things that will raise it, like how close the antenna is to the imperfect earth below the antenna system.&nbsp; In a vehicle those both play their parts and modify the feed point impedance, as well as the antenna&#039;s radiation resistance.&nbsp; I agree that the number most people shoot for, namely 50 ohms, isn&#039;t really what they think it is, but at the same time, 36 ohms isn&#039;t necessarily the number to shoot for either.Those are also not the only things that affect impedance, as well as the antenna&#039;s radiation resistance.Not having the models myself it is hard to say, but the model with more wires seems to be less efficient and more directional, at least as far as the models you posted are concerned.&nbsp; The maximum gain figure isn&#039;t all you need to be looking at, but the entire pattern, and in the case of these models the side gain as well, which is listed and noticeably different.&nbsp; The patterns don&#039;t look anything alike, so aside from the gain numbers appearing to be about the same, I would definitely not call them similar.As I stated above, 0.96 AGT, and that was just how it ended up, I didn&#039;t have to modify the model in any way.&nbsp; Actually modifying various aspects of the model didn&#039;t actually change the AGT, so it seems pretty stable, more so than other models I have made in the past.<a href="http://hittman.us" target="_blank">The DB</a></blockquote>

[QUOTE="The DB, post: 578832, member: 21346"] I'm not, mainly because of the results I got with my first attempt at modeling my vehicle. I'm getting an AGT of 0.96, I think the larger number of elements are actually helping here. That 36 ohm number, there are exactly three cases that that is relevant. [LIST=1] [*]If you are mounted over a perfect ground, (that is a 1/4 wavelength antenna with the other half being the perfect ground, not a ground plane antenna mounted some distance above perfect ground) good luck with that irl. [*]If you are over an analog of a perfect ground, such as, say, 120 ground plane radials of 1/4 wavelength. That would be an 18 foot diameter ground plane, good luck fitting that on a car. [*]The things that affect the antennas feed point impedance just happen to balance each other out and give that as a result, but how do you know that happened? [/LIST] Regarding number 3, impedance is a funny thing, there are things that will lower it, such as not enough metal underneath the antenna, you know, like on all vehicles that are road legal, and things that will raise it, like how close the antenna is to the imperfect earth below the antenna system. In a vehicle those both play their parts and modify the feed point impedance, as well as the antenna's radiation resistance. I agree that the number most people shoot for, namely 50 ohms, isn't really what they think it is, but at the same time, 36 ohms isn't necessarily the number to shoot for either. Those are also not the only things that affect impedance, as well as the antenna's radiation resistance. Not having the models myself it is hard to say, but the model with more wires seems to be less efficient and more directional, at least as far as the models you posted are concerned. The maximum gain figure isn't all you need to be looking at, but the entire pattern, and in the case of these models the side gain as well, which is listed and noticeably different. The patterns don't look anything alike, so aside from the gain numbers appearing to be about the same, I would definitely not call them similar. As I stated above, 0.96 AGT, and that was just how it ended up, I didn't have to modify the model in any way. Actually modifying various aspects of the model didn't actually change the AGT, so it seems pretty stable, more so than other models I have made in the past. [URL='http://hittman.us'][COLOR=#000000]The DB[/COLOR][/URL] [/QUOTE]

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