Speed over ground (SOG) Speed log with built in STW sensor

  • Speed over ground (SOG) in three axis (Docking mode)
  • Speed through water (STW) in one axis
  • Colour 9\\” touch screen with day/night screens and Compact dot LED display
  • NMEA 0183 output
  • LAN
  • GPS, GLONASS (SOG) and Doppler speed (STW)

The SKIPPER combined speed log SD21 is a three axis speed log and a one axis speed log providing both SOG and STW. It is providing longitudinal and fore/aft transversal ship speed over ground (SOG) in additional to longitudinal speed through water (STW). The SKIPPER combined speed log SD21 provides accurate navigation parameters measured as they happen, and presented in a logical, user friendly way.



Log Combined speed log SD21 Units
Number of Axis
  • 3 + 1
Speed range longitudinal
  • +/-99,9 from Satlog
  • +/-40 from doppler
Speed range transversal
  • +/-99,9 from Satlog
  • N/A from doppler
  • Dual GLONASS/GPS’ speed (SOG)
  • Single axis doppler speed (STW)
  • Transmitting Heading Device (THD).
  • GNSS type NV08C-CSM.GPS L1 : 1575.42 MHz.GLONASS L1: 1602.0 MHz for Fk=0 where k= (-7 to +13) channel spacing 562.5 kHz
Bottom track All depths meter
Accuracy (better than)
  • <0.2 or 2% whatever is greater
Power Supply
  • AC:115/230 VAC
  • DC: 20-32 V
Power Consumption
  • Display 5W
  • Electronic unit 10W
  • Multi – PanelPC 9\” touch display, Resolution 800×480
  • 28×30 pixel Alphanumeric LED (red) for STW
IP rating display
  • 2x
IP rating antenna
  • 66
Mounting Dimensions
  • Graphic display – 224,5 mm wide x 140 mm high
  • Dot matrix display – 124×124 mm. Bracket or panel mounting
  • Antenna – 100 mm height, 180 mm width, 780 mm long
  • 1.2 kgs, Graphic display
  • 1,8 kgs, dot matrix display for STW
  • 3 kgs antenna
  • 4 kgs electronic unit
  • English
  • Year-month-day/hour-min (taken from GPS)
Cable needed
  • Not included.
  • 40 m included for STW sensor
  • 4 TSP (Twisted, shielded pairs) Min 0.5mm. Max length 100m
  • Outer cable dimension 10-14mm
NMEA Outputs
  • VLW: Distance travelled over ground.
  • VTG***: Actual course and speed relative to the ground.
  • VBW: Dual ground/Water speed
  • DDC Dimming command output
  • GPS Gyro and status
  • HDT*: Actual vessel heading in degrees True produced by any device or system producing true heading.
  • ROT*: Rate of turn and direction of turn.
  • THS*: Actual vessel heading in degrees True produced by any device or system producing true heading.
  • GSA**: Satellite DOP and active satellites.
  • GSV**:Number of satellites in view,satellite ID, elevation, azimuth and
  • SNR.Postion and time signals
  • GGA*: Time, position and fix related data.
  • GLL*(***):Longitude and latitude of vessel position, time of position fix and status.

*This sytem is speed log and cannot be used as primary source of other types of information.

** Only available on the LAN port

*** Position, course over ground and heading is only to be used as secondary sources

  • 2xLAN (IEC61192-450)
  • 4xNMEA0183 Output (IEC61192-1)
  • 2xNMEA 0183 Inputs (IEC61192-1)
  • Made to IMO performance standard
  • Available in most major harbours, world-wide through extensive dealer network
Navigation Speed Logs