The VLF band is used for a few radio navigation services, government time radio stations (broadcasting time signals to set radio clocks) and for secure military communication . Since VLF waves can penetrate at least 40 meters (131 ft) into saltwater, they are used for military communication with submarines.
Read moreWhat are very low frequency waves?
Very low frequency (VLF) is a radio frequency band in the range of 3 to 30 kHz with wavelengths from 10 to 100 km . It is also the name of the band designated by the International Telecommunication Union (ITU).
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