>You can go for max gain, max F/B, or the compromise of the two however
>you like without having to worry that optimization on 14.015MHz will
>make the pattern junk at 14.250MHz.
>I don't know how much of a practical difference that ends up making.
>Someone who has designed more yagis might comment... I think it
>matters quite a bit in some instances.
Designs with a lot of superdirectivity would tend to fall in this
category, since they are notoriously sensitive to small changes in
dimensions. One could actually analyze it: there's a theoretical
maximum gain for a given boom length (with infinite number of
elements). The closer you are to that gain, the more likely you are
to benefit from adjustible elements.
At some point, though, IR losses will dominate the whole thing, no
matter what you do with the element lengths.
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