>
> > Based on information that Roger Cox of HyGain has previously posted
> > to the Towertalk group, putting the boom broadside to the wind is
> > best of HF antennas.
>
> Not so fast!
>
> ON4UN's excellent book Low Band Dxing (an ARRL publication) is much
> clearer on the subject. In section 13 paragraph 3.3.4.1 he writes:-
> "If the area of the boom is smaller than the area of all the
> elements, then put the boom perpendicular to the wind. And vice
> versa......"
Since you are quoting my post, don't leave out the important part.
I posted Roger's listing of boom and element areas for a wide range
of Hy-Gain antennas (from the smallest 3 element 10 meter monobander
to the big TH-11) and in every case save for a 6 element 6 meter
monoband antenna there was more wind area in the elements than in
the boom.
> It is clear that if you have a short boom HF antenna, the elements
> will have a higher wind load, but for a multi-element and therefore
> long boom antenna, the boom has the higher wind load. You need to
> calculate to decide which applies to you.
Even the Hy-Gain 205CA (a five element monoband antenna on a 32 foot
boom) has more than twoce as much area in the elements than in the
boom (205CA: elements 11.5 ft^2 boom 5.8 ft^2)
> These things are NOT a matter of opinion as some contributors seem to
> think. Do some number crunching and work on the basis of FACT!
That's right ... get your facts straight first!
>
> .
> ,--_|\ Morrison Hoyle - vk3bcy@dcsi.net.au
> / Oz \ - Phone +61 (0)3 56891205
> \_,--\_/ - PO Box 248, FOSTER, Vic 3960 Australia
> v
>
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>
>
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