4. NMEA 0183 Connections
For an NMEA 0183 interface (as opposed to an NMEA 2000 connection), use a small terminal block to connect the transmit-positive and transmit-negative wires on the supplied power/accessory cable to corresponding wires on the chart plotter. Check the chart plotter manual to identify these receive-positive and receive-negative wires.
5. Connect Power
Route the positive wire with a 3-amp in-line fuse from the power/accessory cable and connect to a switchable 12-volt power source, such as the breaker switch for the marine electronics. Connect the negative wire to an onboard negative bus bar or other grounding source. Wait until all other connections are made before powering up the AIS.
6. Configure the System
Power up the AIS and chart plotter, and access the plotter setup menu to display AIS data. Check the plotter manual for the proper steps. AIS vessel signals show as triangles and aids to navigation show as squares. Scroll over a symbol to read information such as a vessel’s Marine Mobile Service Identification (MMSI) number, vessel name, speed and course.
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.