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Much of the site is devoted to the enormous overhead wire antenna array that is necessary to efficiently radiate the VLF waves. The antenna, shown above, consists of ten catenary cables, 5,640–8,700 ft (1,719–2,652 m, 1.1–1.6 miles) long, suspended in a zigzag pattern over the valley between Wheeler mountain and Blue mountain on twelve 200 ft. towers on the mountains' crests.
Notable elements include updated Extremely High Frequency (EHF) communications satellites, and redundant Very Low Frequency (VLF) communication paths for strategic message traffic. The changes will resolve problems associated with aging or ineffective devices such as pagers, klaxons, and Emergency Action Message (EAM) processing systems.
The transmitters include those designed to operate at Very Low Frequency (VLF). The submarines pick up the message via special antennas. Nuclear-capable forces will then be expected to carry out an EAM without fail. Crewed bombers may be recalled, but missiles fired from land-based silos or from submarines cannot be recalled.
VLF transmissions of Morse code to ships close to U.K. in the 1980s; now used as a military high frequency radio transmitting station FTA2: Saint Assise, France: 16.9 kHz, [5] 20.9 kHz [1: La Regine (FUG) Villemagne, France: 62.6 kHz
A VLF receiving antenna at Palmer Station, Antarctica, operated by Stanford University. Very low frequency or VLF is the ITU designation [1] [2] for radio frequencies (RF) in the range of 3–30 kHz, corresponding to wavelengths from 100 to 10 km, respectively.
The Very Low Frequency (VLF) antennas are large spider webs of wire supported in a top hat arrangement. The centre tower 'Tower Zero', rises to a height of 387.4 metres. The other towers are spread out in two concentric rings around Tower Zero; the towers of the inner ring are 303.5 metres high while those of the outer ring are 358.
The E-4C Survivable Airborne Operations Center (SAOC) is a United States Air Force program to develop a replacement for the E-4B National Airborne Operations Center (NAOC), a strategic command-and-control military aircraft used as a mobile command post for the National Command Authority in emergency situations.
Boeing EC-135C Looking Glass. Looking Glass (or Operation Looking Glass) is the historic code name for an airborne command and control center operated by the United States. In more recent years it has been more officially referred to as the ABNCP (Airborne National Command Post). [1]