[TowerTalk] Lightning protection - length of grounding rodsruns from tower?

[Patrick Greenlee]

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 rods
>> while 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 on
>> paper...
>>
>> Ray,
>> N6VR
>>
>>
>>
>> On Thu, Jan 29, 2015 at 11:36 AM, john at kk9a.com <john at kk9a.com> wrote:
>>
>>> Less effective than what?  Two 8' ground rods 8' apart are less 
>>> effective
>>> than a single 8' rod?
>>>
>>> John KK9A
>>>
>>>
>>> To:     "Jim Lux" <jimlux at earthlink.net>
>>> Subject:        Re: [TowerTalk] Lightning protection - length of 
>>> grounding
>>> rodsruns from tower?
>>> From:   charlie at thegallos.com
>>> Date:   Thu, 29 Jan 2015 11:37:40 -0500
>>>
>>>
>>> I can't think of a good way to word it - except may to say a pair of 
>>> rods
>>> closer than 2x is less effective -
>>>
>>> _______________________________________________
>>>
>>>
>>>
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>