The use of a high-gain television transmitting aerial in a populous area

The paper is concerned with the provision of satisfactory signals to viewers in the immediate vicinity of the Crystal Palace television station, where an 8-tier aerial is sited in an urban area. The problem was complicated by differences between the halves of the aerial, but a satisfactory performance was ultimately obtained. The only serious discrepancy between theoretical and experimental results could be removed by taking account of reflection at the ground, ignoring the effect of buildings. In order to provide continuity of service in spite of any single breakdown, the halves of the aerial were originally supplied from separate transmitters; this arrangement had to be abandoned, since it proved impossible to provide undistorted signals at receiving points where the contributions from the transmitters were in phase opposition.