Telemetry of tidal data

A system is described which acoustically telemeters data from a bottom-mounted recording tide gauge to a moored surface buoy and from there makes the data available via a VHF radio-telemetry link to a survey ship within a 25 to 35 km radius. The system can be easily deployed from the survey ship and enables tidal data to be obtained during the course of a survey, particularly in areas where the installation of near-shore tide gauges is impractical. Parameters of the tide gauge, the acoustic transmitter and receivers the radio telemetry equipment and the shipboard readout equipment are presented. Testing and use of the system is discussed.