摘要 |
<p>The microphones are spaced at specified distances, and a transmitter is mounted in a float from which runs a second cable to a device receiving signals from the microphones and applying them to the transmitter. A propellor (27) is attached to the end of the first cable (37) which moves it in a specified direction. A parachute (26) resisting this movement is attached to the other cable (37) end. An electronic unit (25) is connected through a secondary cable (24) to the transmitter float (22) which has an antenna (45) in the form of an upwards projecting spike.</p> |