21. Satellites can track an individual ship easily, and even submarines are usually detected by hydrophone arrays. 22. "Venturer " s hydrophone operator noticed a strange sound which he could not identify. 23. Hydrophone sensor systems are used by the oil industry as well as a few countries'navies.24. When a hydrophone / transducer receives a specific interrogation signal it responds by transmitting a specific reply signal. 25. Data is transmitted from the sensors using wireless acoustic telemetry and is received by a hull mounted hydrophone . 26. In air, sound pressure can be measured using a microphone, and in water with a hydrophone . 27. Purely from the standpoint of detection, towed hydrophone arrays offer a long baseline and exceptional measurement capability. 28. Launders tracked the U-boat by hydrophone , hoping she would surface and allow a clear shot. 29. Working with researchers, they will record dolphin sounds by hydrophone and take notes about their markings and behavior. 30. Depth charge rails were installed in the stern and a Type 93 hydrophone set was fitted in the bow.
