Dear Panos,
Thank you for this good information. I have added it to my new web site at
http://www.w0btu.com/files/antenna/Optimum_no_of_radials_vs_radial_length.html
73,
Mike Waters
www.w0btu.com
> From: Πανος Δαλάκος <pdala@tee.gr>
> Subject: Topband: Optimum number of radials for given wire length
> To: topband@contesting.com
> Date: Thursday, August 12, 2010, 5:45 PM
>
...
> I have the ARRL's ANTENNA BOOK 20th Edition, and on Chapter
> 3 (The Effects of the Earth), p.3-10 is Table 1 tht maybe contains
> all you want about that.
> If you haven't the book here is the table:
>
> Number of radials
> 16 24 36 60 90 120
>
> Length of each radial in
> 0.10 0.125 0.15 0.20 0.25 0.40
> wavelengths
>
> Spacing of radials in degrees
> 22.5 15 10 6 4 3
>
> Total length of radial wire
> 1.6 3 5.4 12 22.5 48
> installed in wavelengths
>
> Power loss in dB at low angles 3 2 1.5 1 0.5 0*
> with a L/4 radiating element
>
> Feed-point impedance in ohms
> 52 46 43 40 37 35
> with a L/4 radiating element
>
> * compared to a perfectly conducting ground
>
> 73 Panos SV1GRD
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