The MD36/8 solid-state digital NMEA to analogue STEP (S-Type) Interface for low power retransmission of digital NMEA heading data

SKU: F036021 Categories: ,


The MD36/8 is a solid-state digital NMEA to analogue STEP (S-Type) Interface for applications where there is a need for low power retransmission of digital NMEA heading data to legacy STEP equipment.

It converts a NMEA 0183 (IEC61162-1) compliant digital transmission to a DC STEP (S-Type) transmission at 24 V, 35 V or 50 V dc to within 1/6° with no errors.

Supplied for bulkhead mounting as standard, the MD36/8 offers a compact NMEA to STEP (S-Type) Interface solution for locations where available space is limited.

Constructed in a robust die-cast aluminium enclosure and finished in RAL9005 Jet Black fine texture powder coat paint, the MD36/8 is designed to complement existing marine navigation equipment.

The MD36/8 STEP (S-Type) to NMEA Interface from MARINE DATA. Designed to be easy to install and simple to maintain.


  • Low-power, high accuracy conversion
  • Accepts standard NMEA 0183 HDT sentence at 4800 baud
  • Three line STEP (S-Type) transmission output, suitable for 24-70 V dc (smoothed or unsmoothed) common negative connection at up to 1 A per STEP line


  • The MD36/8 is suitable for converting from digital NMEA 0183 (IEC61162-1) transmission format to any STEP (S-Type) transmission format. This is especially useful for retro-fitting legacy systems with modern equipment requiring a digital transmission of ships heading
  • The MD36/8 forms an integral part of MARINE DATA Heading Repeaters supplied for use with STEP (S-Type) transmission systems


  • The MARINE DATA Range of Compass Repeaters
  • MD86HCU Heading Comparator Unit


  • Weight: 1.0 kg
  • Dimensions: H 222 mm; W 146 mm; D 55 mm
  • Mounting: Bulkhead mounting
  • Connections: 3x M20 Cable Glands; M4 Earth Stud
  • Construction: Aluminium alloy enclosure
  • Finish: Jet Black (RAL9005) Fine texture powder coat paint


  • Power Supply: 24 V dc nominal; 50 W nominal; 18-32 V dc
  • Data input: RS422; NMEA 0183 (IEC 61162-1) $HEHDT,xxx.xx,T*CS 4800 Baud; up to 20 messages per second
  • Data output: STEP (S-Type), 3 Line, common negative, 24‑70 V (nominal) STEP supply, smoothed or unsmoothed, 1 A per line
  • STEP Power: STEP Power to be provided by installer


  • Performance: 1/6° accuracy (limit of STEP signal)
  • MTBF >30,000 hours


  • IP rating: IP54
  • Operating temp: -15°C to +55°C
  • RoHS Compliant
  • Compass : Safe distance 50 cm


  • Conforms with: IEC 60945 IEC 61162-1


  • Option: Custom paint colour
  • Option: Stainless steel cable glands – subject to MOQ

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