Provides heading and positioning information using Global Navigation Satellite Systems (GNSS) including GPS and GLONASS.


The MD203 GNSS Compass delivers heading and positioning information, and provides unparalleled continuous performance using Global Navigation Satellite Systems (GNSS). The robust, rugged housing is sealed for the harshest environments. It incorporates fixed and pole mounting capability for both marine and land applications.

The MD203 supports both NMEA 0183 and NMEA 2000 protocols and the unit delivers accurate and continuous performance, including position, heading, heave, pitch, and roll. Integrated gyro and tilt sensors give fast start-up times and heading updates.

During periods of short satellite signal loss, the inertial sensor automatically takes over as the prime source for heading determination until the GNSS comes back on line.

The MD203 is capable of replacing several vessel instruments with one compact navigation tool. The stability and maintenance-free design replaces traditional gyrocompasses and stand-alone GPS units at a fraction of the cost.

Note: When used for type approved applications, the MD203 must be connected to the MD203MFD Multi Function Display via LAN.


  • True heading anywhere on earth
  • 0.5º heading accuracy
  • Heading accuracy unaffected by the latitude
  • Heading available in periods of GNSS drop-outs
  • Compliant to WAAS, EGNOS and MSAS Satellite Based Augmentation Systems
  • Replaces several instruments with one robust, integrated product
  • Only paired cable (no coax) between the mast unit and the equipment on the bridge
  • 20 Hz update rate on heading, rate of turn and position measurements (configurable)
  • Output of data on Ethernet
  • 1PPS out synchronisation signal


  • Provides a source of NMEA 0183 Digital Heading Data to be used as a replacement, or alongside the Marine Data Transmitting Heading Device (THD) System; an alternative (or a backup) system to a gyrocompass as a source of Heading.