Characteristics and adjustment of 335-megacycle equisignal glide slopes

The equisignal glide slope is produced by radiation from two aerials, an upper placed directly above a lower at several times its height. The r.f. power applied to the aerials is modulated at 150 and 90 c/s respectively. The first main lobe from the lower aerial encompasses several lobes from the upper aerial and the intended glide slope is formed where the first lobe from the upper aerial intersects the lower side of the first lobe of the lower aerial. The characteristics of the sending and airborne receiving equipment and of the true nature of the radiation patterns, are given.