Wide-band folded-slot aerials

Among the possible applications of Babinet´s principle proposed by C.E.G. Bailey and H.G. Booker was the ¿folded slot,¿ the slot analogue of the well-known folded dipole. The paper describes modified forms of folded slot designed to exhibit reactance compensation, so that the variation of impedance over a wide band of frequencies is small. Calculation of the input impedance is facilitated by considering an equivalent circuit which applies to certain types of 3-terminal network. The bandwidth of an aerial for multi-channel f.m. broadcasting has been improved by the use of folded slots.