[TowerTalk] vertical antennas

K3BU@aol.com K3BU@aol.com
Sun, 4 Nov 2001 19:39:22 EST


In a message dated 11/2/01 11:08:56 AM Eastern Standard Time, K3BU@aol.com 
writes:

>  aa4lr writes:
>  >  Now, pi/2 wl divided by 50 is pi/100 -- which is 0.0314159..., and pi/2 
>  >  wl divided by 60 is pi/120 -- which is 0.02618. Close, but not quite 
>  >  0.025.
>  
>  Simple, 
>  Tom is (always) right, you are using wrong Pi(e :-)
>  
>  Yuri
>  
Actually it is a little less.
Just to be more precise and not to accumulate errors while lying out radials 
:-)

AA4LR example is valid for the length of the arc with radius of the radial 
length, being .25 wavelength and that is 0.02618 wl.

Proper formula for the straight distance A between the tips of the radials 
(length R) and number of radials N is

A = 2R sin 180deg/N

so for 60 radials .25 wl. long

A = 2 x 0.25 x sin 3deg
A= 0.5  x 0.052335956
A= 0.026167978 wl.

For those who want to be precise, as they say, hope it helps.

Yuri, K3BU
visit antenna forum at Radiofest Nov 10 in Glen Spey NY
<A HREF="http://www.verkhovyna.com/radiofest.htm">Radiofest</A> 

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