Antenna Calculators

Quick tools for antenna design calculations

Ground Plane — 4NEC2 Generator

λ/4 vertical + N elevated radials → .NEC file with SY variables

Dipole Calculator

Total Length = 142.65 / f(MHz)

Quarter Wave Calculator

Length = 71.325 / f(MHz)

Radial Calculator

Radial Length = 71.325 / f(MHz)

End-Fed Transformer Calculator

Turns Ratio = √(impedance ratio)

SWR Calculator

SWR = (1 + √(Pr/Pf)) / (1 - √(Pr/Pf))