This calculator will calculate the radiation resistance of a Marconi antenna which is short compared to the wavelength. Formulas are taken from this excellent page by ON7YD.

Enter antenna height in metres:

Enter antenna horizontal segment length in metres:

Enter frequency in MHz:

Enter antenna impedance (dominated by ground loss plus inductor loss) in ohms:

Enter transmitter power output in watts:

The wavelength in metres is:

The radiation resistance in ohms is:

The antenna efficiency is:

The approximate antenna capacitance in pF is:

The required inductance in uH is:

The antenna current in A is:

The antenna voltage in V is:

The total radiated power in watts is:

The EIRP in watts is:

Back to calculators page or main page.