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Why is it said 1/2 wave dipole antennae have 73 Ω resistance + 43 Ω reactance? How can they generalize like that?
4 Answers
- BillLv 73 years agoFavorite Answer
perhaps those values were found by actual measurement of half wave dipoles for a wide range of frequencies, when the dipole is in air more than 1/2 wave from the ground.
- amania_rLv 73 years ago
The equation that gives those values is in the link below.
The feedpoint impedance does vary with the height of the dipole from the ground. That effect is dependent on the frequency.
- PhilomelLv 73 years ago
The impedance of freespace is 377 ohms. an antenna is supposed to match the impedance of the transmitter to freespace for maximum power transfer.
