Topband: Optimum number of radials for given wire length

[Mike Waters W0BTU]

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 at tee.gr>
> Subject: Topband:  Optimum number of radials for given wire length
> To: topband at 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