Hello Ron:
You might want to take a look a my QST article about the Lazy "V" array that I
used and was published in the early 90's.
I installed the K8UR array and the full sloper K1THQ array prior to settling on
the design that I worked on with WA3FET and K3LC (QST article). Both UR and THQ
arrays had disappointing results at my QTH.
Good Luck and 73!
Tim K3LR
Ron Feutz wrote:
> Topbanders,
>
> I have long wanted to put a K8UR array (1/2 wave dipole 4-square with
> center fed elements pulled back in at the bottom) or a similar array using
> straight dipole slopers, on a 240' SSV commercial 2-way tower that I
> own. The tower scales up nearly exactly from the 80 meter array in ON4UN's
> book. I have a Comtek 4-sq controller that I intend to use.
>
> ON4UN does not show baluns at the feed points; the Comtek manual does. Are
> baluns necessary? I would prefer to not use them to lighten the wind and
> weight load on the antenna/tower.
>
> The pattern shown in John's book for the K8UR array has a very broad front
> lobe and a poor front-to-back, making the array a less-than-ideal RX
> antenna. Is there anyone using one who could give me advice on this? I
> lease only a small plot where the tower sits, and don't know if I could get
> permission to put RX antennas nearby.
>
> The pattern for the array with straight sloping dipoles shows a sharper
> front lobe and a much better F/B, but it has lots of high angle radiation.
> It seems to be a trade off, but my gut tells me the straight dipole sloper
> array would be a better RX antenna.
>
> Is there anyone out there who could model this for me? It would be nice to
> know the right length for the dipoles at the start, as cut-and-try would be
> a very cumbersome tuning method.
>
> 73,
>
> Ron - WA9IRV
>
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