At 04:08 AM 2008-12-02, Martin Sole wrote:
>Cebik mentions quite emphatically that to ensure decent performance from
>a 5 band quad, or any that involve multiple bands, it is necessary to
>ensure that the driven elements of the un-fed bands are shorted. In
>essence, when operating on 10m the 20m loop looks like a 2 wavelength
>loop and will have significant currents in it unless it is closed.
Whether you short a nearby 2 wl quad element or leave it open, it
will still be resonant and carry a fair amount of current. I think
the benefit of shorting the element is that the currents are
symmetrical and cause less skew of the elevation pattern.
If you have the link or the title for a Cebik article that discusses
shorting the lower band elements, I'd appreciate it. The search
engine on cebik.com gives far too many hits to wade through if you
search for "5 band quad".
73, Terry N6RY
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