Coupling for VHF aerials mounted on same pylon - has quarter wavelength radius conducting disc mounted on pylon between transmitter and receiver aerials

摘要

The aerials are mounted on the one pylon at different heights and have a decoupling coefficient of 70 dBs, operating in the range of 150-220 MHz. A decoupler, in the form of two conductor discs, is located midway between the two aerials. The discs are mounted coaxially, with each disc having a radius of a quarter wavelength. The discs are spaced apart by a quarter wavelength distance and the aerial is equidistant from the pylon foot and the discs. The discs have a thickness of 4mm. The aerials are pref. half-wavelength dipoles, each having two back-to-back reflector screens.