An AIS (Automatic Identification System) receiver is essentially a black box that plugs into a chart plotter and lets you identify, locate and read important safety data about vessels and aids to navigation broadcasting AIS signals. There are a number of models from Furuno, Garmin, Icom, Raymarine and others. We chose the compact Si-Tex MDA-2 Metadata Dual Channel AIS receiver ($258.99, defender.com), which measures 5½ inches wide by 4 inches high by 1¾ inches deep.
Getting Started
Time to Complete: 4-5 Hours
Skill Level: 4/5
Tools and Supplies:
* AIS black-box receiver
* VHF antenna and ratchet-mount base
* NMEA 2000 T-connector ($19.95, thegpsstore.com)
* NMEA 2000 backbone cable ($24.95/6½-foot, thegpsstore.com)
* Two-circuit terminal block for NMEA 0183 connection ($3.89, westmarine.com)
* In-line 3-amp fuse
* Marine crimp-on ring terminals and butt connectors
* Cable clamps and tie-wraps
* Wire cutter
* Wire stripper
* Crimper
* Power drill and drill bits
* Screwdrivers
* Socket wrench set
Quick Tip
AIS signals are broadcast over line-of-sight VHF radio frequencies. So as with VHF radio, the taller the AIS antenna, the better the signal reception and the sooner you will see an AIS-broadcasting vessel on the chart-plotter display. However, remember that not all vessels are broadcasting AIS, and so it should not be used to replace, but rather to supplement, prudent navigational procedures.