As for a 40M and 80M antenna; it depends on what range you are wanting to
maximize your signal (NVIS or DXing with a low angle of radiation). For
NVIS, a low dipole is by far the best choice. For DXing, ideally you would
like a dipole 1/2 wave length or higher. I read somewhere "the *dipole
should* always be at least 20 feet *higher* than the *height* you were able
to achieve". Since dipoles 1/2 wave length or higher on 80 and 160 are out
of the question for most amateurs, for DXing we default to verticals (or
phased verticals) with there inherent low angle of radiation.
The couple of issues with verticals. They need an effective radial system;
2 or 4 tuned elevated, or the most ground radials you can lay out (60 or
more). Unless you are erecting it over saltwater, you will not have very
good results without an effective radial field. The second issue is being
vertically polarized they are noisy, and unless you have a seperate receive
only antenna(s), that may or may not be an issue at your QTH.
if you can't erect a descent vertical antenna (full size with 60 or more
1/4 wave radials) go with a dipole as high as you can get it. Am not a
bit surprised by Gedas's experience with a dipole at 70 ft on 40M (about
1/2 wave length above ground) and the short vertica with no really
efficient ground radials. Several years ago, I wanted to play around on
60M. With no place to erect a dipole at a descent height for 60M, I erected
a DX Eng 30M, 1/4 wave length vertical (43 ft). After laying down about 64
or so 43 ft ground radials, I called it a day. Have to say I have been
quite pleased with its performance.
Dick, K8ZTT
On Tue, Aug 27, 2019 at 3:52 PM Phil <pmills7@comcast.net> wrote:
> My personal experience with the R9 was not good. I'd been
> a Cushcraft fan for years and when my R8 got trashed I
> decided to put the R9 to have the 80 meter coverage.
>
> First, the antenna is tall and you really need to have the
> upper portion guyed or it won't stand a severe storm. Then,
> the instructions give no information on the adjustment of
> the 80 and 40 meter coils, so I assembled the antenna with
> my coils set as the factory shipped them. The swr on both
> 80 and 40 was terrible...well over 5 to 1. 20 meters and up
> had very low swr.
>
> I would recommend this antenna only if you can guy it and if
> you have a place were you can set it up and take it down easily
> until you get the 80 and 40 meter coils tuned to your satisfaction.
>
> 73, Phil W5BVB
>
>
> On 8/27/2019 10:44 AM, John Groom wrote:
> > Slightly off target subject but does anyone have experience with the
> Cushcraft R9 or the Hygain AV680 verticals. Looking for a wireless 40-80
> option for winter while my tower is renovated. Thanks in advance all. John
> WB8LXE
> >
> > Sent from my iPhone
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