Advertisement

Understanding AIS Systems

Get the benefits of AIS on board: Gear up to receive signals and display the data.

ytgaug21newelect5251.jpg

Dialed In

A truly different Class B is Simrad’s AI50 ($1,627), which plots targets on its own four-inch color display and can even record voyage and AIS history to a memory card. It also has “buddy tracking,” which means that it will highlight preselected vessels when they come within range. A nifty advanced AIS feature: If the AI50 is connected via its SimNet/NMEA 2000 port to a similarly equipped VHF radio, a simple command can use a target’s MMSI to “autodial” its DSC VHF radio. There is also an NAIS300 black-box version of this transponder available from Simrad and other Navico brands.

Simrad USA, (425) 778-8821; **www.simradyachtingusa.com**

Advertisement

Plotting Powerhouse

| | |

The original Coastal Explorer earned a stellar reputation, especially for its adept AIS plotting, and the major 2009 version update ($399) raises the bar significantly. It can, for example, display DR “shadows” for targets that update their position slowly, as well as scale them to true dimensions when zoomed in. And it interfaces easily with every NMEA sensor I’ve tested it with, be it AIS, GPS, wind speed and direction, rudder angle, and more. In fact, it’s an excellent overall PC charting program, supporting multiple chart formats including free NOAA raster and vector formats, which it can update automatically. It’s also very good at planning, featuring easily downloaded weather data and simply searched guidebooks, and even a way for cruisers to share points of interest and photos.

Advertisement

Rose Point Navigation, (425) 765-2976; **www.rosepointnav.com**

All Ears

| | |

Advertisement

Skippers who just want to monitor AIS targets, but not be one, can get a simple receiver. However, these devices are unregulated and hence they vary significantly. Icom’s new MXA-5000 ($499) monitors both of the AIS frequencies simultaneously, just like all transponders do. Some current receivers just listen to one frequency at a time, a difference that will become quite noticeable as slow-talking Class B transponders proliferate. The unit also has a built-in low-loss antenna splitter, which will simplify installation, and it delivers target data via the NMEA 0183 standard, which can be understood by most any current multifunction display or PC charting system.

Icom America, (425) 454-8155; **www.icomamerica.com**

Advertisement
Advertisement