Data sample recording system
Depth sound indicator
Depth sounder
Depth sounder with indicia lighting means
Determination of variations of wave characteristics
Device controller
Device for communicating with a system
Direction determination in sonar systems
Discriminating sonic detection system
Diver navigation system
Diver's pulse stretch sonar
Doppler navigation method for determining the distance travelled
Doppler spectral measurement
Doppler speedometer
Dopplerizing a signal of varying frequency
Dual beam sonar display system