----- Original Message -----
From: "Ron Feutz" <feutz@wctc.net>
To: <topband@contesting.com>
Sent: Wednesday, July 16, 2003 2:23 PM
Subject: Topband: New 4-square
> Gentlemen,
>
> I recently moved to a new QTH and plan to build a new 4-square.
>
> My antenna field is 175' wide X 500' long, and is heavily wooded. An
> asphalt driveway runs roughly down the middle of the antenna field.
> The long lot lines run directly N/S. A traditional 1/4 wave per side
4-sq,
> with the sides parallel to the lot lines, would be properly oriented NE,
> SW, etc. There would be 2 elements on either side of the driveway with
> short radials towards the sides and middle of the lot (E-W) and longer
ones
> towards the ends (N-S). Because of the compromise radial system I would
> want to connect the 4 elements' radial systems together.
>
> Questions:
>
> 1. My ground system and phasing lines will have to cross the driveway. I
> can do one of the following: Run buss wires along both sides of the
> driveway and connect the radials to the buss wires and then either go up
> and over the driveway (about 8' or so) to connect the systems together
with
> a relatively few wires, or bore under the driveway ( I don't know how this
> is done or how much it would cost) to connect the systems together. Would
> the up and over method cause any performance problems or pattern
> disruptions? It would be easy, as there are plenty of trees available for
> supports (the driveway is only 8' wide).
>
The up and over has problems. The impedence of the radials is very low, and
I am afraid the up and over would be like an RF choke. These radials are in
parallel with others, and the "others" would hog the current. I would cut a
few slits in the driveway for the wires (or a slit for the feeds and just
lay the radials on top) and have the black-top man come and cover them up.
John K9DX
>
>
>
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