Breed's design (now patented) had only one element driven as a dipole.
The elements for the other frequencies (three total in his WARC example
that you mentioned) were "closely coupled resonators", and not driven
directly. A swept frequency return loss plot showed very unique spikes
at each designed frequency of interest.
73,
Brad, W5CGH
==========================================
--- n4kg@juno.com wrote:
> K9AY published an article on a 3 band
> wire dipole for the WARC bands in RF Design several years ago
> (Nov 1994). He suggests conductor spacing (d) according to
> this formula:
>
> Log (d) = 0.54 x Log (D/4) where D = conductor diameter
>
> (assuming equal D for each element).
>
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