Seawater antennas

The US Navy is looking for a way to replace bulky antennas on warships with antennas made from seawater.

What they came up with is little more than an electromagnetic ring and a water pump. The ring, called a current probe, creates a magnetic field through which the pump shoots a steam of seawater (the salt is a key ingredient, as the tech relies on the magnetic induction properties of sodium chloride). By controlling the height and width of the, the operator can manipulate the frequency at which the antenna transmits and receives. An 80-foot-high stream can transmit and receive anywhere from 2 to 400 mHz, though much smaller streams can be used for varying other frequencies, ranging from HF through VHF to UHF.

Wow. (via bldgblog)

• physics
• science
• water