GB530406A - Improvements in or relating to radio antennae - Google Patents

Abstract

530,406. Directive wireless signalling. MARCONI'S WIRELESS TELEGRAPH CO., Ltd. June 22, 1939, No. 18250. Convention date, July 28, 1938. [Class 40 (v)] A directive aerial with a wide band characteristic, suitable for transmitting or receiving television signals, consists of a multiple-V arrangement, the various elements being effectively in parallel though the wires may be connected in series, each leg of each V consisting of a pair of closely-set wires. As shown in Fig. 3, each. of the legs A, B is an odd number of eighths of the working wavelength. In Fig. 5 the length of the legs is the same, though the inside pair B, B includes a surge impedance at the apex ; this gives a particularly wide band characteristic. In Fig. 4 the legs are each an integral number of half-waves in length, and the inside pair are open-ended. The wires may be of different diameters. Owing to the close spacing of the wires, the radiation characteristic is equivalent to that of a single dipole though the radiation resistance is quadrupled. This means, in practice, that no impedance-matching coupling is required between the aerial system and the feedline TL. Specification 500,162 is referred to.