Making Sense Out of NMEA 0183 and NMEA 2000


[Editor’s note]. This article is a sidebar to the article “Networking the Old and New,” that appeared in the January 2019 issue. Use our search bar to find additional articles on onboard networking.  

The NMEA 0183 has two different communication (baud) rates for-4800 baud and the faster 38400 baud (also known as NMEA 0183-HS). You have to match the baud rate of both devices for communication to occur. AIS will always use the faster rate. Once the speeds correlated on our test boat, the radio presented targets on its one-inch display. Sitting at the dock it was apparent that info below decks was useless.

  1. Standard Horizons GX2150 Matrix AIS+ has internal GPS which allows it to track position and deliver AIS data, but the screen is too small to be of much use in rough conditions.
  2. Images 2 and 3 are from the instruments on the test boat (yes she was going slow). The Raymarine autopilot is getting navigation information (bearing to waypoint) from the Garmin
  3. GPS position data is generated by the Garmin chartplotter/GPSmap 440s.
Practical Sailor has been independently testing and reporting on sailboats and sailing gear for more than 45 years. Supported entirely by subscribers, Practical Sailor accepts no advertising. Its independent tests are carried out by experienced sailors and marine industry professionals dedicated to providing objective evaluation and reporting about boats, gear, and the skills required to cross oceans. Practical Sailor is edited by Darrell Nicholson, a long-time liveaboard sailor and trans-Pacific cruiser who has been director of Belvoir Media Group's marine division since 2005. He holds a U.S. Coast Guard 100-ton Master license, has logged tens of thousands of miles in three oceans, and has skippered everything from pilot boats to day charter cats. His weekly blog Inside Practical Sailor offers an inside look at current research and gear tests at Practical Sailor, while his award-winning column,"Rhumb Lines," tracks boating trends and reflects upon the sailing life. He sails a Sparkman & Stephens-designed Yankee 30 out of St. Petersburg, Florida.


  1. Just subscribed to Practical-Sailor and found this ‘article’ and agree with the comments so far. Title implies much more than is addressed. And even what is written does leave the reader guessing whether something went wrong with the hit ‘publish’ button. Hope this is not a trend…..

  2. This article is a short sidebar to the main article “Networking the Old and New,” ( that appeared in the January 2020 issue. The entire issue, including additional images to illustrate the topic, can be downloaded here Additional Practical Sailor reports on onboard networking can be found using the search bar at the top.


Please enter your comment!
Please enter your name here