Speed Log (JLN-741)

Speed Log

  • Highly accurate speed and distance log
  • Proprietary bubble detection
  • 10.8VDC to 31.2VDC
  • Cost-effective display


The JLN-741N is a cost-effective doppler speed log with a 4.5-inch display with the main data displayed in large characters of easy reading. In addition that the display is fully dimmable and has backlit keys, it features dual LED backlight (white and orange) making it easy to operate in various light settings on the bridge.

The JLN-741N is a single axis water SDME compliant with the IMO MSC.96 (72) standard, required on all internationally voyaging ships exceeding 300 GT. Boasting never-before-seen accuracy for speed measurement, the JLN-741N is also installed with our company’s proprietary bubble detection function, which informs you when measurement accuracy is impaired due to air bubble contact.

A long-unsolvable problem with doppler-based water speed measuring systems was reduced accuracy from bubbles making contact with the measuring device on the bottom of the vessel. The JLN-741N series detects when bubbles contact the transducer, and using roprietary technology from JRC alerts you of reduced measuring accuracy via the display. Confirming the source of the issue typically requires visually examining the device on the bottom of the ship. However, onboard air bubble detection allows you to skip unnecessary preventive maintenance.

We are a family owned and operated business with over 100 years of experience

Please feel free to contact to discuss your requirements in more detail, we would be delighted to assist you.

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