From http://www.coastalradio.org.uk/melbourne.htm

The "Flying saucer" Biconical monopole transmit antenna. It was transferred to Melbourne Radio from
 Hobart radio when Hobart closed. Not often used, because it caused interference to the station
 receivers - It was sited too close to the main station building. A very complex antenna to rig,
 and quite dangerous - A rigger was injured during installation.