Working of Echo Sounder
- The recorder sends a signal to the pulse generator which triggers a pulse and simultaneously starts the recorder trace.
- The rate may be between 5-600 pulses a minute depending upon the depth to be measured.
- Lesser the depth scale, faster the Pulse Repetition Frequency.
- The pulse from the Pulse Generator activated the transmitter which sends a powerful electric pulse to the Transducer.
- The transducer converts the electric energy into sound energy producing a pulse.
- The sound energy travels to the bottom, hits the bottom and gets reflected back to the transducer.
- The transducer converts the received sound energy of the echo into an electric pulse and sends it to the receiver.
- In the receiver the received pulse is processed and then amplified and sent to the Recorder.
- At the recorder, the stylus which has been at a speed proportional to the speed of sound, creates a physical mark on a paper or a visual blip or a digital signal for the recorder.
What is Transducer of Echo-Sounder?
- Magneto-Striction is an effect which occurs in all ferromagnetic material, but particularly pronounced in iron, nickel and cobalt.
- These items when placed in a magnetic field change their length.
- Conversely, when subjected to physical stress they generate an emf.
- When alternating current is used to create a magnetic flux, the transducer will vibrate producing a sound pulse.
- Sighting of the Transducer
- Away from noise sources and areas of turbulence like the propeller and discharges.
- Away from aeration which is caused due to bubbles generated by the bow wave or irregularities on the hull, log tubes and discharge orifices.
