In a message dated 97-01-13 13:17:47 EST, you write:
>The recent mention of Force antennas reminds me of a question that's
>been rattling around for some time. I keep hearing the C3 referred to
>as a set of monobanders sharing a single boom. There are six loaded elements
>but no traps, so this appears to translate to three two element yagis
>interlaced on a boom. How could these yagis possibly compete with the
>other trapped yagi designs that have 4-5 active elements per band? What
>am I missing?
>
Hi, Pete --
Well, not really monobanders in the strict sense of the word but they
are all parasitic on different frequencies. Since gain is a function of boom
length, that's where you need to start. And that's irregardless of the
number of elements. The more elements you have on a given boom length aren't
necessarily going to give you any more gain. The Force 12 antennas have been
computer modeled and optimized so they compete very well (and sometimes
better) with a comparable trapped tribander of similar boom length. You may
want to get a copy of Tom's book, "Array Of Light", that gets into more
design details. Along with a lot of other interesting topics, as well.
BTW, I don't think the elements are "loaded". They're parasitic but do
not have any traps or additional loading on them.
73, Steve K7LXC
TOWER TECH -- professional tower supplies and services for amateurs
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