This tool calculates the physical dimensions of a 20 meter (m) dipole antenna.
20 m refers to the wavelength of the transmitted and/or received signal.
Using the calculator below at 20 meters,
- the dipole length (L) is 31.2 feet
- the length of each element of the dipole (l) is half of that at 15.6 feet
Formula
The total length (L) of the dipole antenna is calculated as:
L = 468 / f
where f is the frequency in MHz.
f is calculated from the wavelength. For 20 m the frequency is 15 MHz.
The length of each arm of the dipole
l = L/2