Best solution is to configure it as a ground plane vertical. They work very
well indeed. Cut 4 pieces of regular telephone cable for a 1/4 wave on the
longest band. Measure from the vertical base point the 1/4 lengths for
each of the higher bands, open the jacket and cut one of the wires to serve
as the 1/4 wave radial for that band. Do this for each successively higher
band. Attach all of them to the ground base of your vertical and you're in
business. Since my vertical was self-supporting, I just used the telephone
cable tied off to the four corners of my roof. It's OK if they droop over
the ends of the roof. For a mast mounted vertical, I used a SS stranded guy
wire as the support guy and messenger cut for the longest 1/4 wave band, egg
insulator, and balance of the guy to the support point. I then hung the
telephone cable from it for the higher bands.
I used this system for several years all over the world and it always worked
very well, especially on 40M. Try one, you'll like the results.
Here is a very good primer on verticals by W4RNL:
http://www.cebik.com/fdim/fdim4.html
Jon Hamlet, W4ZW
Casey Key Island, Florida
"A little piece of paradise in the Gulf of Mexico"
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jason Reber
> Sent: Saturday, December 09, 2006 11:53 AM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Roof Counterpoise
>
> Greetings Everyone-
>
> I would like to set up a vertical antenna at my QTH, but my
> small backyard is arranged such that it is impossible to set
> up a good radial system. In addition, my house is right in
> the middle of the yard, so the best place to put the antenna
> would be on my roof.
> Rather than running radial wires all over my roof, I was
> wondering if anyone on the list has tried making a
> counterpoise system by placing wire mesh (such as rabbit
> wire) on the underside of the roof in the attic? I have easy
> access to the underside of the roof, so the mesh could be
> stapled (using short staples, of course) right to the roof
> sheathing underside. The pieces of mesh would all be tied
> together to create a large counterpoise.
> I have not been able to find much information about the
> effectiveness of such a counterpoise in the Antenna book, or
> from other source, so I would welcome anyones experience or advice.
>
> Thanks,
>
> Jason AC7JW
>
> _______________________________________________
>
>
>
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