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From: DavidC[SMTP:davidc@bit-net.com]
Sent: Wednesday, July 08, 1998 4:40 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Quad vs Yagi
David: A few years ago I put up a stack of six triband yagis on a rotating 190
foot Rohn 55G tower. For the next 18 months or so I got a big thrill out of
playing DXpedition working Europeans hour after hour contest style.
When ever a station came back that was 10 or 20 dB over the top of the pileup,
I made a habit of asking what the antenna system was. Invariably, the most
common response was either a stack of yagis or a quad. I have had it happen so
often that I have become a believer in the idea that the quad definitely has a
lower angle of radiation than the typical yagi at the same elevation.
I realize that when I model the quad vs. yagi on the computer that I don't see
this difference, but I am only honestly reporting what I have observed from a
relatively rare perspective.
73/Mike, N7ML
You may want to have a look at the May 1979 and May 1982 issues of Ham
Radio magazine. Wayne, N6NB, has a lengthy study of yagis versus quads and
generally concludes that there is little true difference. I was somewhat
persuaded, though I still find many testimonies from actual users with both
types of antennas side-by-side which suggest otherwise.
Two of the most common advantages stated for quads are better performance
at lower heights and better performance at the opening and closing of the
bands due to conditions (this is said to be because the quad is quieter and
thus hears better).
L.B. Cebik, W4RNL, has a very enlightening discussion of antenna height
versus performance at his web site: http://web.utk.edu/~cebik/hsyg.html
Perhaps some of his work might be helpful in calculating maximized
performance heights for yagis and quads.
I have decided to put up one KLM KT-34XA and one tri-band quad and see what
I can discover!
Hope this helps a little ... 73, DavidC AA1FA
> Name is Randy KK7TV. I have a kt34xa and a 40c2 on a rotating
> tower. They are both KLM's. I have had them up for 12 years. I am
> thinking of building a Quad, 4 elements on a 30 foot boom. 10-20
> including WARC. I know the 40 m beam must come down. I have compared
> my signal with a ham close to me that has the same quad I want to
> build. We tried 20-17-15 m.
> He smoked me to Europe and to VK ZL and over the pole. In the morning,
> evening and late night.
> I am convinced that my system is working good so I can rule out faulty
> gear. Has anybody else
> tried this with a close-by ham?. What do you think, a quad will hold
> up fine here in AZ and I can lower the tower for the stormy season.
> BTW if you want to see the shack it is on the web site listed below.
> Thanks for all your thoughts.
> Best 73
> Randy
>
> --
> Randy Starace
> KK7TV Communications
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