To: | towertalk@contesting.com |
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Subject: | Re: [TowerTalk] Lightning protection - length of grounding rodsruns from tower? |
From: | Patrick Greenlee <patrick_g@windstream.net> |
Date: | Fri, 30 Jan 2015 08:35:04 -0600 |
List-post: | <towertalk@contesting.com">mailto:towertalk@contesting.com> |
Geometry seems to have an intuitive feel to it and is less intimidating
than Trigonometry. There are demonstrations on the web of how to
CONSTRUCT a hexagon, an octagon and other figures using only a straight
edge and a compass.
Just scale the construction to accommodate the radius of coverage desired for each rod and get the actual dimensions right off the drawing. This is easy to do and is more accurate than needed. It has been a couple years but I used some of these methods successfully in woodworking projects. Patrick NJ5G On 1/30/2015 8:00 AM, Roger (K8RI) on TT wrote: You are also limited on more shorter runs as the distance between runs will have the first rod or two on adjacent runs fairly close. The first rods a couple of feet out will by necessity be close.Refresh your math skills and try to do it with trig <:-)) They come from a common point (center of the tower. 6 radials would be 360/6, or 60 degrees forming the vertex of an equilateral triangle and that about exhausts my math abilities. So that's where my refreshing would start. Refreshing? What am I saying? I never had Trig in the first place! I have a math minor without ever having taken trig and I graduated in 90. I never had to use a bit of it since then. So the sum of my knowledge is the same as before I took all those classes. It looks good on a resume, but I never claimed to be any good at it.73 Roger (K8RI) On 1/30/2015 1:24 AM, Ray Benny wrote:Thanks to all who made comments.My take away is to use more shorter ground rod runs from the tower, say 30- 40 ft, than a smaller number of longer runs. I will see how many 30 ft radial runs I can make using 8 ft ground rodswhile keeping 16 ft separation between the rods. Guess I could pull out a drawing compass and scale the radials lengths, then measure between the 16 ft points. Boy, this make me old! Haven't done this in ages, especially onpaper... Ray, N6VR On Thu, Jan 29, 2015 at 11:36 AM, john@kk9a.com <john@kk9a.com> wrote:Less effective than what? Two 8' ground rods 8' apart are less effectivethan a single 8' rod? John KK9A To: "Jim Lux" <jimlux@earthlink.net>Subject: Re: [TowerTalk] Lightning protection - length of groundingrodsruns from tower? From: charlie@thegallos.com Date: Thu, 29 Jan 2015 11:37:40 -0500I can't think of a good way to word it - except may to say a pair of rodscloser than 2x is less effective - _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk_______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk |
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