Folded Dipole Antenna

 Folded dipole antenna was a common sight on roof tops, as the driven element of TV antennas a few decades back. In a folded dipole antenna, a half-wave length conductor is folded into a longitudinal loop and fed at the centre. It has a higher impedance of around 280 Ohms compared to the 70 Ohms impedance of a horizontal half-wave dipole antenna. Hence while a coaxial cable is suited for a horizontal half-wave dipole antenna, a twin-lead transmission line with about 300 Ohms impedance is used for a folded half-wave dipole antenna.


73 de Jon, VU2JO

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