Topband: K8UR array

[James Wolf]

Tim,
 
W9LT experimented with this (parasitic) design back in the 70's.
Whether or not he was working from his own idea, I don't know. I believe it
was published as I still remember the pictures with his home in the
background, but I can't recall which pub.
I played with one of these arrays at my QTH on 40 meters in the early 80's.
I finally ended up with a horizontal dipole at 60 ft, roughly the same
height as the top of the Lazy-V.

If you want this configuration to perform, you need to phase the elements in
a 4 sq configuration.
K9UWA is using a phased version on 80 meters and it consistently outperforms
much a higher dipole.
 
A search on the ARRL web site shows K7LR wrote something in 1966, but alas,
I don't have those resources.
Keywords: ANTENNA WIRE HF CONSTRUCTION HOMEBREW Leo, Bob, W7LR
Dec 1966 QST 34 V.H.F. Lazy-H Antenna, A
(Gimmicks and Gadgets) DeMaw, Doug, W1CER 

Tim, can you share what design you finally settled on?

James Wolf, KR9U



> 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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