GP calculator

This calculator is designed to give the vertical length (height) of a quarter wave ground plane antenna, and the length of each of the four radials (often called radiators) for this frequency. The normal quarter wave ground plane antenna consists of a vertical radiator which is insulated and centered between 3 or 4 horizontal surrounding radials which extend out from the base of the antenna. Each radial is evenly spaced around the vertical element.
 
Enter the desired frequency, click on Calculate and the optimum length for that frequency will be displayed in meters, feet, and inches.
 
To optimize the antenna for a frequency RANGE, do the calculations twice, once for the low end of the range and once for the high end.
Then average the two and plan to adjust the VSWR on both ends of the range as needed.
 
Required Data Entry
Desired Frequency Mhz
   
Calculated Results
Vertical Length (Mtrs)
Vertical Length (Feet)
Vertical Length (Inch)
Radial Length (Mtrs)
Radial Length (Feet)
Radial Length (Inch)
 
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version 6.02.11   Source