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@ RFoutput,
Thank you for pointing that out!
Im sure he will be just using the antenna for lisning if it isnt allowed in his country

@Marconi,
Bare in mind: SWR does not tell anything about GAIN/Front to back / efficiency.
I wouldnt recommend to just change the driven element distance towards the reflector as that is quite critical. Not only do you change the resonant frequency it doesnt have the effect on bandwidth as you think it migth have.
As i read your post (i could be wrong) you draw that conclusion by going over the 3el and 4el version. If that is the case please dont, they are two different antennas and changing element spacing will have different effect on both.

Maximum gain for a antenna design can indeed been seen as a bad design for many.
The good thing is, often with a reduce in maximum gain (just a couple tenths of a dB)
in most cases you can produce good results. And no one will notice that sligth difference in forward gain.

Im not sure how thick the elements are of the wilson but if they are different from the sirio
If i recall correct wilson is quite large and sirio isnt, though i could be wrong.
You will also get different results compared to any other that you have had in the past.

It is possible to get a 50 Ohms antenna with 8,4dBI and 23 FB. A SWR bandwidth of 2 Mhz (but again that bandwidth does not tell you if the gain and FB is high over that region).

Narrow spacing is never "primarily" for gain. WIDE spacing is.
Wide spacing resolves into the biggest boomlength. The longer that is the more gain you have. Boomlength is primarily (not alone) responsible for gain.

The 4el Sirio is for "normal" antenna terms perhaps a bit on the small side.
A 3elements yagis these days on a similair or sligthly less boom (3,6 meter instead of 4m) will do exactly the same when you look at gain/FB.

Im not sure what has happend to some of your "optimized" designs.
If you call them almost "omnidirectional". That would also implicate it has no gain.
Perhaps i can have a look at them?

Regards,

Henry
11 meter Dx antenna systemx

<blockquote data-quote="Henry HPSD" data-source="post: 256813" data-attributes="member: 2333">@ RFoutput,Thank you for pointing that out!Im sure he will be just using the antenna for lisning if it isnt allowed in his country <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f642.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":-)" title="Smile&nbsp; &nbsp; :-)"&nbsp; data-smilie="1"data-shortname=":-)" />@Marconi,Bare in mind: SWR does not tell anything about GAIN/Front to back / efficiency.I wouldnt recommend to just change the driven element distance towards the reflector as that is quite critical. Not only do you change the resonant frequency it doesnt have the effect on bandwidth as you think it migth have.As i read your post (i could be wrong) you draw that conclusion by going over the 3el and 4el version. If that is the case please dont, they are two different antennas and changing element spacing will have different effect on both.Maximum gain for a antenna design can indeed been seen as a bad design for many.The good thing is, often with a reduce in maximum gain (just a couple tenths of a dB)in most cases you can produce good results. And no one will notice that sligth difference in forward gain.Im not sure how thick the elements are of the wilson but if they are different from the sirio If i recall correct wilson is quite large and sirio isnt, though i could be wrong.You will also get different results compared to any other that you have had in the past.It is possible to get a 50 Ohms antenna with 8,4dBI and 23 FB. A SWR bandwidth of 2 Mhz (but again that bandwidth does not tell you if the gain and FB is high over that region).Narrow spacing is never &quot;primarily&quot; for gain. WIDE spacing is.Wide spacing resolves into the biggest boomlength. The longer that is the more gain you have. Boomlength is primarily (not alone) responsible for gain.The 4el Sirio is for &quot;normal&quot; antenna terms perhaps a bit on the small side.A 3elements yagis these days on a similair or sligthly less boom (3,6 meter instead of 4m) will do exactly the same when you look at gain/FB.Im not sure what has happend to some of your &quot;optimized&quot; designs. If you call them almost &quot;omnidirectional&quot;. That would also implicate it has no gain.Perhaps i can have a look at them?Regards,Henry <a href="http://www.19sd348.nl" target="_blank">11 meter Dx antenna systemx</a></blockquote>

[QUOTE="Henry HPSD, post: 256813, member: 2333"] @ RFoutput, Thank you for pointing that out! Im sure he will be just using the antenna for lisning if it isnt allowed in his country :-) @Marconi, Bare in mind: SWR does not tell anything about GAIN/Front to back / efficiency. I wouldnt recommend to just change the driven element distance towards the reflector as that is quite critical. Not only do you change the resonant frequency it doesnt have the effect on bandwidth as you think it migth have. As i read your post (i could be wrong) you draw that conclusion by going over the 3el and 4el version. If that is the case please dont, they are two different antennas and changing element spacing will have different effect on both. Maximum gain for a antenna design can indeed been seen as a bad design for many. The good thing is, often with a reduce in maximum gain (just a couple tenths of a dB) in most cases you can produce good results. And no one will notice that sligth difference in forward gain. Im not sure how thick the elements are of the wilson but if they are different from the sirio If i recall correct wilson is quite large and sirio isnt, though i could be wrong. You will also get different results compared to any other that you have had in the past. It is possible to get a 50 Ohms antenna with 8,4dBI and 23 FB. A SWR bandwidth of 2 Mhz (but again that bandwidth does not tell you if the gain and FB is high over that region). Narrow spacing is never "primarily" for gain. WIDE spacing is. Wide spacing resolves into the biggest boomlength. The longer that is the more gain you have. Boomlength is primarily (not alone) responsible for gain. The 4el Sirio is for "normal" antenna terms perhaps a bit on the small side. A 3elements yagis these days on a similair or sligthly less boom (3,6 meter instead of 4m) will do exactly the same when you look at gain/FB. Im not sure what has happend to some of your "optimized" designs. If you call them almost "omnidirectional". That would also implicate it has no gain. Perhaps i can have a look at them? Regards, Henry [url=http://www.19sd348.nl]11 meter Dx antenna systemx[/url] [/QUOTE]

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