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[QUOTE=&quot;EscapeVelocity, post: 46085, member: 3771&quot;]When you get the Kosmic SuperQuad, you can cut the Bowties down to 9 and then 8 inches while reducing the interbowtie feedline spacing and see if that increases gain on VHF High, with a spectrum analyzer.My testing has shown little difference.&nbsp; The Bowties being broadband elements and 8 to 10 inches being very close to 1/4 waves at VHF High.&nbsp; The difference being a shift from 1/4 wave at the center of the VHF HIGH band to the extreme low side of VHF HIGH band....which is a better configuration.&nbsp; But the spectrum analyzer is more precise as a measuring instrument than anything I have here.&nbsp; 9&quot; to 10&quot; is a sweet spot in that regard, however my design also is concerned with UHF performance, and the 10&quot; whisker length is beneficial for the extreme low end of UHF, which drop off dramatically in these 8&quot; and especially the 6.75&quot; bowtie elements of the 8 bays and 4 bays, that came before it.The CM 4221HD increases gain at the extreme low end with its 24&quot; wide reflector....which is a full wave at those frequencies.The Kosmic SuperQuad uses a 28&quot; reflector which also has reinforcing effect as a full wave wave reflector at the very low end of UHF....though not as tuned as the 24&quot;.&nbsp; But that is because I am also concerned with VHF High.&nbsp; A 36&quot; ish reflector is nice because its 3/2 waves at the extreme low end of UHF, and 2 waves at mid UHF television band.&nbsp; And is also 1/2 wave at the lower end of VHF High.&nbsp; Its better to err to the low side of a band, as its better to have a slightly long element than a slightly short element.&nbsp; Which can be seen with dipole plots off resonance....of the bowties for example.&nbsp; Which is the reason for their gain plunges at the low end of UHF.&nbsp;&nbsp; So 9.5&quot; whiskers with a 36&quot; reflector is a good place to be.&nbsp; 10&quot; with a 28&quot; is a compromise off of that, but it is also a good place to be.&nbsp; 10&quot; cheats toward the low end of both UHF full wave and VHF High 1/4 wave, and 28&quot; is high end of VHF High (center band with wire lengthening effects), and is full waveish at extreme low end of UHF, plus 3/2 waves at mid UHF band.Given the choice of $60 shipping for the 36&quot; screen, and $20 for the 28&quot; screen, the choice was clear.That is my story and Im sticking to it.[/QUOTE]

[QUOTE="EscapeVelocity, post: 46085, member: 3771"]When you get the Kosmic SuperQuad, you can cut the Bowties down to 9 and then 8 inches while reducing the interbowtie feedline spacing and see if that increases gain on VHF High, with a spectrum analyzer. My testing has shown little difference. The Bowties being broadband elements and 8 to 10 inches being very close to 1/4 waves at VHF High. The difference being a shift from 1/4 wave at the center of the VHF HIGH band to the extreme low side of VHF HIGH band....which is a better configuration. But the spectrum analyzer is more precise as a measuring instrument than anything I have here. 9" to 10" is a sweet spot in that regard, however my design also is concerned with UHF performance, and the 10" whisker length is beneficial for the extreme low end of UHF, which drop off dramatically in these 8" and especially the 6.75" bowtie elements of the 8 bays and 4 bays, that came before it. The CM 4221HD increases gain at the extreme low end with its 24" wide reflector....which is a full wave at those frequencies. The Kosmic SuperQuad uses a 28" reflector which also has reinforcing effect as a full wave wave reflector at the very low end of UHF....though not as tuned as the 24". But that is because I am also concerned with VHF High. A 36" ish reflector is nice because its 3/2 waves at the extreme low end of UHF, and 2 waves at mid UHF television band. And is also 1/2 wave at the lower end of VHF High. Its better to err to the low side of a band, as its better to have a slightly long element than a slightly short element. Which can be seen with dipole plots off resonance....of the bowties for example. Which is the reason for their gain plunges at the low end of UHF. So 9.5" whiskers with a 36" reflector is a good place to be. 10" with a 28" is a compromise off of that, but it is also a good place to be. 10" cheats toward the low end of both UHF full wave and VHF High 1/4 wave, and 28" is high end of VHF High (center band with wire lengthening effects), and is full waveish at extreme low end of UHF, plus 3/2 waves at mid UHF band. Given the choice of $60 shipping for the 36" screen, and $20 for the 28" screen, the choice was clear. That is my story and Im sticking to it.[/QUOTE]

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