VLF Transmitter Woodside

VLF Transmitter Woodside

Woodside Omega Transmitter (station G, now Woodside VLF transmitter) near Woodside, Victoria, Australia at 38°28′52″S 146°56′07″E / 38.481228°S 146.935294°E / -38.481228; 146.935294 uses an umbrella antenna carried by a 432 metre high grounded lattice steel guyed mast. Unlike many of the other Omega Transmitters, Woodside is not a "hot tower," that is, one which is insulated from a ground connection by large ceramic insulators that support the entire weight of the structure. Rather, the tower is electrically insulated from the topmost guys which served as the radiators, similar to the metal radials of an umbrella without cloth covering. The mast simply supports the downward sloping guy wires which are the active elements. The guy wires also are used to hold the tower itself in place. This mast is the highest structure in the southern hemisphere. Construction of this station was originally planned to be built in New Zealand but after protests from anti-war protestors it was built in Australia.

After the shutdown of the OMEGA navigation system it was used until 2004 as a transmitter for uni-directional communications to submarines on 13 kHz under the callsign VL3DEF. Until December 2008, it had been transmitting a 100 baud MSK modulated signal on 18.6 kHz.