Hello Roger:
Here is the wiring diagram you are looking for.
Raymarine RN300 wiring
Battery negative black -12 VDC
Battery positive red +12 VDC
NMEA in+ white DB9 pin 3 (data out)
NMEA in- green DB9 pin 5 (signal ground)
(not connected) gray
NMEA out+ yellow DB9 pin 2 (data in)
NMEA out- brown DB9 pin 5 (signal ground)
(not connected) (screen)
Must turn off simulator to get NMEA to start.
NMEA sentences can be select/deselected for output.
Jeffrey Atwood
