Dipole Antenna

The half wave dipole is the most basic antenna one can think of and it can be the base component of a more complex antenna. The feedpoint impedance of a half wave dipole in free space is 73+43j ohms. To cancel the inductive reactance the dipole is usually made slightly shorter. For a infinitely thin wire the factor is 0.98 and it drops to 0.94 for thick conductors. This calculator uses a typical factor of 0.95. The antenna height over ground, antenna materials etc. will have an effect, so this calculator will not give an exact measure. Finally you have to tune the lengths by trial and error to get the desired results.