> Amazing how the same antenna can produce two different results,
> depending on who makes the test.
>
> It's my understanding a large part of Lindsey's error in giving the
> quad 2 dB gain over a similar boom-length yagi were caused by a
> combination feed system, measurement, and scaling errors.
>
> Yet that article was the start of this entire mess.
> 73, Tom W8JI
> w8ji@contesting.com
>
[Dave D'Epagnier] Well it appears to me that a 2 element Quad does
have about a 1dB gain advantage over a 2 element Yagi. Look at Cebik's
analysis in the two articles "What Can We Expect From a 2-Element Beam?
Parts 1-5 (5-9-97)" and "New Quad Studies (2000-2001)". It's pretty evident
that the 2 element quad beats the 2 element Yagi both in gain and front to
back especially if wide diameter elements are used. Front to back is much
better with the quad. So far I have heard nothing from this discussion that
would indicate that the quad is inferior electrically to the Yagi. In fact,
just the opposite. Mechanical considerations are a different matter, but die
hard quad users insist that they can be made pretty bullet proof. Does the
quad have a 2dB advantage? No. Does it have any advantage? Well the computer
models say yes and in the antenna world every tenth of a dB improvement is
significant and hard won.
--Dave
K0QE
>
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