On Sunday, January 18, 2015 at 8:16:04 PM UTC-6, wrote:
wrote:
On Sunday, January 18, 2015 at 4:08:31 PM UTC-6, Bruno wrote:
On Sun, 18 Jan 2015 21:28:07 +0000, jimp wrote:
Verticals; if you have a lot of area, phased vertical arrays.
Aren't verticals more inclined to generate interference?
BTW, my plot is 120' by 90' so I think an array at HF will be impossible.
The feed point will be pretty much central to the plot, though.
I would probably string up parallel coax fed dipoles and have them at
the low height. IE: 18-20 feet off the ground if that's all you can do.
They will still work fairly well overall. Say if you can stick a short
1-2 ft stub mast on the roof, run dipoles from it, and feed with a single
coax for both bands. Run the legs out to wherever you can tie them off.
IE: trees, or short masts in the back yard/garden, etc.
Won't be a gang buster DX setup, but plenty good enough for general use.
With 40 and 20 dipoles, you would also have 15 meters, running the
40 legs. And you can feed more dipoles from the same coax if you
want more bands.
Using the coax as a feed line, no tuner required and low system losses.
And also no need to worry about laying out radials.
At that height most of the energy goes straight up, so it will be a
NVIS antenna mostly suited for short ranges.
--
Jim Pennino
Sure. But it will still be able to work some DX, particularly on 20m,
and 15m using the 40 legs.
I guess it depends a lot on the type of operating he does.
If he wants general purpose, and maybe more leaning to NVIS for 40m
rag chewing, I'd go the dipole.
If he wants DX over NVIS, he may well be better off with a vertical.
But even a low dipole can be fairly good on the higher bands.
I remember camping once with a 40m dipole about 8-10ft off the ground,
and having no trouble working JA's on 15m using the same low antenna.
For 40m NVIS within 500 miles or so, the low dipole will likely smoke
most verticals.
I've run so many low dipoles, I can't count them all. Never had trouble
operating with any of them. And the setup is fairly simple.
The thing about verticals, they tend to be fairly lackluster for closer
in work on the lower bands. And I work much more rag chew NVIS type stuff
than DX. I'm actually not interested in DX much at all any more.
Been there, done that.. So it's kind of boring to me these days..
I tend to mostly jibber jabber to people I know these days, and work mostly
close in 160/80/40.. Which for my type of operating, the dipoles usually do
a good bit better than the verticals, even if fairly low.
I guess he'll have to decide what he wants to lean to. Whatever he decides
is unlikely to excel at both, and will be a compromise.