46° 5'3"N 90°54'55"W Former Clam Lake Extremely Low Frequency (ELF) transmitting station.
The ELF transmitter site was composed of 2 ground dipole antennas, each 14 miles long, extending in 4 directions from the central transmitter site.
This station transmitted signals at 76 Hz to communicate with submerged US nuclear submarines worldwide.
Clam Lake site was operational between 1985 - 2004 and has been replaced by newer systems.
The antennas have been removed.
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