Date: Fri, 20 Feb 2015 22:26:59 -0600
From: "Keith Dutson" <kdutson@sbcglobal.net>
To: "'Pete Smith N4ZR'" <n4zr@contesting.com>,
<towertalk@contesting.com>
Subject: Re: [TowerTalk] Tribander Spacing
Thanks Pete. Your spacing is only 28 feet, less than a half wavelength on
20. I also had a recommendation of 5/8 wavelength on 20. That calculates
to 41 feet. I was thinking 35 feet. Guess I need to put it in HFTA to see.
73, Keith NM5G
## For folks with crank up towers, like the UST-HDX 589 or 689 variety, there
is another option.
With the top triband yagi say 6-10 feet above the top of the tower.....and a
tic ring at the 55 ft level, you
would have 40-44 feet of separation. This should work for 20m. By
lowering the tower a bit, the
separation can be better optimized on both 15m + 10m. Since all the 4 x
upper sections reduce by the same amount
at the same time, you would not lose a lot of height on the lower yagi either.
IE: top yagi at 75 feet, then the lower yagi
would be at 45 feet..with 30 ft separation.... assuming in that case, top yagi
mounted 6 ft above the top of the tower.
Jim VE7RF
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