Paul,
The trees should not affect the performance of the 4-square. However, the
trees and scrub growth could make it very difficult or impossible to lay out
a buried or "on-the-ground" radial system. For best performance, you should
have about 60 radials per element. It's OK to route the radials around trees
and other obstructions (i.e., the radials don't have to be perfectly
straight), but that only works if the trees are far enough away from the
elements so that adjacent radials don't touch one another. The radials get
very close together near the elements, so you can't have any trees there.
Lots of scrub, especially close to the antennas, will interfere with laying
out the radials. My guess is that it would be a nightmare trying to do that.
You can cut down the number of radials so that they are farther apart, but
that will reduce the efficiency of the antenna. I wouldn't use less than 30
per element.
Another alternative is to elevate the verticals and use an elevated radial
system. Quite a few people have had success with just 2-8 elevated radials
per element. This should work for you if you can get them above the scrub.
However, I would avoid getting them too close to the trees. My understanding
is that a lot more current flows in the wires of a system like this and
there could be a fire hazard at high power (someone on the reflector can
flame me about that if I'm wrong.) Another issue is the real performance of
an elevated radial system. Although there have been articles claiming that
elevated radial systems work as well as ground radial systems, I've seen
data suggesting that elevated systems need to be really high (1/4
wavelength?) in order to approach the efficiency of ground radial systems.
Anecdotal evidence on the reflector also suggests that a ground radial
system is superior. However, if an elevated system is all you can do, then
that's the way to go. The system will certainly work.
In my case, I had the land cleared and laid 240 radials on the ground.
73, Dick, WC1M
-----Original Message-----
From: pramey@bellsouthwd.com <pramey@bellsouthwd.com>
To: towertalk@contesting.com <towertalk@contesting.com>; W7NN <W7NN@aol.com>
To: <towertalk@contesting.com>
Date: Wednesday, May 06, 1998 8:55 AM
Subject: Re[2]: [TowerTalk] 4-Square Owners & Experts...
> I would like to install a 4-Square system but have a question . I
> live on a wooded lot. It has a lot of scrub growth and some full
> sized tree's. Can a 4-Square system be installed with out clearing
> too many of the tree's? How close to the antenna can I have tree's?
>
> Paul
> WG0G/W2
>
>
>--
>FAQ on WWW: http://www.contesting.com/towertalkfaq.html
>Submissions: towertalk@contesting.com
>Administrative requests: towertalk-REQUEST@contesting.com
>Problems: owner-towertalk@contesting.com
>Search: http://www.contesting.com/km9p/search.htm
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|