MV BLUEFIN QUALITY MANUAL - Australian Maritime College

Australian Maritime College
JRC JLN-203 DOPPLER LOG SYSTEM
Start up
APPENDIX 1.9
BRIDGE – DOPPLER LOG
1. Turn on power.
2. The three – digit readout indicates speed instantly.
3. Reset the distance run before departure.
Note: If power is lost to the Doppler the audible alarm will be activated.
Note: The ARPA radar obtains the speed thru water from the JRC JLN Doppler log.
The JRC JLN-203 Doppler log uses a high accuracy pulse Doppler system and high
frequency ultrasonic signals.
Signals are reflected from approximately 1.8 to 3 meters below the hull bottom they are
tracked to detect their Doppler frequency shifts, ensuring a highly accurate measurement
of own ships speed through water without being affected by following seas.
Append 1.9 - Doppler.docx 1
Revised: November 2010