Topband: Partial Radial System

[Carl K9LA]

Tom W8JI said

>As far as I know the low angle 
>signal is affected by things at a pretty good distance, out 
>to perhaps 2 WL or more.
>
NCJ ran a feature by Al K3LC in the Sep/Oct 2006 issue showing how the 
gain of a vertical antenna at various elevation angles depends on ground 
away from the antenna. The results showed that ground at 14 wavelengths 
away (7,504ft on 1.835 KHz) is important for a 1 degree elevation angle. 
Ground at 2.7 wavelengths away (1,448ft) is important for a 5 degree 
elevation angle. Ground at 1.4 wavelengths away (750ft) is important for 
a 10 degree elevation angle. Ground at 0.7 wavelengths away (375ft) is 
important for a 20 degree elevation angle.

As Tom said, your radials affect your efficiency - not the low angle 
gain. The low angle gain is determined by ground a lot farther away than 
a typical radial system.

Carl K9LA