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MD97TMC: Transmitting Magnetic Compass (TMC) System

SKU: MNE-0027


The MD97TMC is a Transmitting Magnetic Compass (TMC) System that detects and also transmits the ship’s Compass Heading over a NMEA 0183 digital connection to one or more Heading Repeaters (Compass Repeaters) at any convenient location on a vessel.
The Calibration Control and Sensor Processor are used to calibrate the Compass Sensor. This is done by turning the ship through 390°. The latest technology accurately processes and converts the compass card position to NMEA 0183 Heading Data.
The Marine Data MD97TMC Transmitting Magnetic Compass System is intuitive to use, and additionally, it is quick and easy to install.


  • Provides Digital Heading Data from a Ship’s Magnetic Compass
  • Simplified system design with just two main components
  • Unparalleled Accuracy; Intuitive Operator Controls
  • Automatic Sensor-to-Compass Calibration
  • Rugged, IP65-rated Magnetic Sensor
  • 2x NMEA 0183 outputs


  • Provides two digital NMEA heading outputs to drive Heading Repeaters (or other devices) at a convenient location
  • An elegant alternative to using an optical reflector in a ship’s magnetic compass installation


  • MD71THD – Control & Display unit provides additional functionality
  • MD54 – Compass Sensor Adhesive Mount
  • MD58 – Compass Sensor Bracket Mount


Increasingly, Maritime Authorities are

accepting the use of Transmitting Heading

Device (THD) Systems onboard vessels.


Marine Data offers two types of THD systems:

•         A system that senses the angular position of a ship’s magnetic compass card, known as a Transmitting Magnetic Compass System (TMC)

•         A system that directly senses the Earth’s magnetic field, known as an Electro-Magnetic Compass System (EMC)

By Marine Data

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Additional information

Item Measurements

MD97CSP: L 146; W 64; D 41 (mm); 0.35 kg
MD52A/B: H 18; Ø 69 (mm); 0.12 kg
Excludes cables & connectors