Although small ground dipoles have been used for years as sensors in geological and geophysical research, their only use as antennas has been in a few military ELF transmitter facilities to communicate with submerged submarines. Besides small research and experimental antennas, four full-scale ground dipole installations are known to have been constructed; two by the U.S. Navy at Republic, Michigan and Clam Lake, Wisconsin, one by the Russian Navy on the Kola peninsula near Murmansk, Russia, and one in India at the INS Kattabomman naval base. The U.S. facilities were used between 1985 and 2004 but are now decommissioned.
