Quick Start Guide for AIT1500 V1.00
Installation Step 4
– NMEA Interfacing
A table showing what each of the 12 wires of the PWR/DATA cable does is printed on the AIT1500 Transponder
and repeated below for your convenience;
Wire colour
Description
Function
RED
Power in +
Power supply connections
BLACK
Power in -
B
LUE
Switch input-
External switch connection for silent mode
WHITE
Switch input+
ORANGE
NMEA0183
port 1 TX+
High speed NMEA0183 output (38,400 baud) intended for
connection to chart plotters
BROWN
NMEA0183
port 1 TX-
TURQUOISE
NMEA0183
port 1 RX+
High speed NMEA0183 input (38,400 baud)
Not normally used
GREY
NMEA0183
port 1 RX-
PINK
NMEA0183
port 2 TX+
Low speed NMEA0183 Output (4,800baud) intended for
connection to other NMEA0183 devices requiring a GPS
feed. Note AIS data is not available on this output.
VIOLET
NMEA0183
port 2 TX-
YELLOW
NMEA0183
port 2 RX+
Low speed NMEA0183 input (4,800baud) intended for
connection to other NMEA0183 compatible sensors for
multiplexing of data to the chart plotter
GREEN
NMEA0183
port 2 RX-
The most common connection to a dedicated chart plotter is to take the NMEA Output 1 ( and Brown
–)
from the AIT1500 Transponder and to connect it to a free NMEA Input on the plotter. You must then tell the chart
plotter that AIS data is connected to this port and set the baud rate to 38,400 Baud
– the standard speed for AIS
data. Consult the instruction manual supplied with your Chart Plotter to understand how this is configured.
The AIT1500 has a second NMEA 0183 output that can be used to pass GPS data to a VHF radio or instrument
system. NMEA Output 2 transmits GPS data at 4800 baud
– RMC, GGA and GGL sentences.
NMEA 0183 data from other equipment can be connected to either of the NMEA Inputs of the AIT1500, although
this is most commonly connected to NMEA Input 2 ( and Green-) at the normal 4800 baud rate for NMEA
0183. This data is then multiplexed with the AIS data and output on the NMEA Output 1 at 38,400 baud and also
on the USB
– useful when connecting to equipment that only has one NMEA input.
Installation Step 6
– USB Interface
When connected to a PC or MAC via the USB cable, the AIT1500 will only get enough power from the computer
to power the microprocessor and the AIS receiver. This allows you to program the MMSI number and other static
data at home or in the office prior to installation. The AIT1500 will not transmit or get a valid GPS position fix
when only powered from the USB interface and the RED Status LED will always be lit when powered from the
USB cable.
If you need to extend the USB cable, please use a USB extension cable that is no more than 4m in length. The
maximum length of USB cable without the use of a powered extender cable or Hub is 5m.
