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Re: [TowerTalk] Radial Question

To: towertalk@contesting.com
Subject: Re: [TowerTalk] Radial Question
From: Jim Brown <jim@audiosystemsgroup.com>
Reply-to: jim@audiosystemsgroup.com
Date: Sat, 27 Feb 2016 16:33:42 -0800
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
You may be fairly close. The wild variable is the soil underneath them and their heights. N6LF recommends doubling the number of elevated radials to further equalize the currents. I have elevated radials on two antennas, and only have four.

73, Jim K9YC

On Sat,2/27/2016 11:43 AM, Robert Harmon wrote:
I use four elevated radials for 80m. What I did was hook up my analyzer to each pair, 90 degrees from one another, without connecting anything else tune for resonance (just like a dipole, which it essentially is) Then connect them all together to the vertical antenna feedpoint coax connection. This worked very well, do I have equal currents in each radial with this approach ?

Bob
K6UJ

On 2/27/16 9:32 AM, Dennis W0JX via TowerTalk wrote:
The effect of the earth on the radial generally is to detune it and make it longer electrically than it is. Perhaps Frank W3LPL can add something here as to why he recommends 70 feet. As for elevated radials. many studies have concluded, going back as far as Les Moxon, that quarter-wave elevated radials are about the worst possible length you can make them. This particular length makes it very difficult to obtain equal currents in each radial. Dick Weber, K5IU, wrote an excellent article on this topic, stating that ideal lengths are 60 degrees (or about 2/3rds of a quarter wavelength) loaded by a single small coil, or 120 degrees (about 4/3rds of a quarter wavelength) tuned by a variable capacitor, are ideal lengths. Of course, a multi-band vertical complicates matters and would require a loading coil for each band.
73, Dennis W0JX
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