Aguada transmission station

Aguada transmission station is a tall guyed radio mast erected by the US Navy. It is used as a facility of the US Navy for transmitting orders to submerged submarines near Aguada, Puerto Rico at 18°23′55″N 67°10′38″W by using radio waves in the very low frequency range.

The Aguada transmission station, originally part of "The Naval Radio Transmitter Facility Aguada", works on very low frequency 40.75 kHz with the callsign NAU. The Naval Radio Transmitter Facility Aguada, apparently consisted of three locations with guyed towers: the primary Aguada transmission station in a 330-acre site; the Naval Radio Receiver at a 242-acre site in Salinas County; and the Naval Radio Transmitter at a 408-acre site in Isabela County. Only the tallest with a height of 367.3 metres is still standing and in use., while the other two were dismantled. It is the tallest structure in Puerto Rico and in the Caribbean region.

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