Membrane transmitter
Membrane transmitters are electrical sounders for lightships and lighthouses with which they emit acoustic signals (fog sound signals, air sound signals or air-fog sound signals) with a specific identifier in invisible weather and fog so that skippers can recognize their position.
A tensioned steel disk is electromagnetically excited to relatively low-frequency vibrations around 500 Hertz , as these enable high sound pressure and a large range. Membrane transmitters are also used as underwater sound signals.
See also
literature
- Oskar Wundram: Mechanical port equipment. Julius Springer, Berlin 1939, p. 155.
Individual evidence
- ↑ Explanations about the ship and the museum. Museum lightship Amrumbank - German Bight ( Memento from September 14, 2012 in the Internet Archive ).