Figure 1: Municipalities in northern Sydney and the TV towers (numbered 1, 2 and 3). Lane Cove, Willoughby and North Sydney form the inner area, and Ryde, Kur-ing-gai, Warringah, Manly, Mosman and Hunters Hill the outer area, of the study. A radius of 4 km from the centre of the towers is shown for reference only.