Tony, I believe you will find it difficult to get the separation needed for
the 4 elements you are sloping off the 68ft center support. See
www.comteksystem.com for the spacing of elements for a 4-square array.
Without good separation you will not get the forward gain nor front to back
and your dumped power will be excessive. No free lunch.
de Joe, aa4nn
----- Original Message -----
From: "Tony Osman" <tony.osman@xplornet.com>
To: <antennaware@contesting.com>
Sent: Tuesday, February 17, 2009 7:43 PM
Subject: [Antennaware] 40m array
>I thought there might be some words of wisdom for me on this list....
>
> I am looking to build a 40m 4-square but currently I am looking at
> mortgaging the house to pay for aluminum - cant seem to find a scrap
> yard anywhere that has any - they are recycling as fast as they can get
> the money for it....
>
> So, I have a 68ft vertical built from 3inch irrigation tubing. Could I
> use this to suspend a K8UR type dipole array? I understand that to get
> the best operation of this array, the coax feeding the dipoles should
> come away parallel to the ground. This means they would connect to the
> vertical at about 25 feet or so off the ground. I would then bring the
> coax down the vertical to the matching box at the base of the vertical
> (of course adjusting the coax lengths to provide correct current forcing
> to each dipole).
>
> My question is - when using the vertical on 80m and 160m (it will have a
> trap at the top of the vertical with top-loading wires for 160m) with
> approx 1KW, will there be any adverse effect on the dipole array or the
> matching network - similarly would these have any effect on the vertical
> for 80/160 operation?
>
> Thanks in advance for any information.
>
> Tony
> Ve3rz
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