Conectar un AIS COMAR a Raspberrypi 3

Yo diria que no recibes datos de barcos:

Operation:
On applying power the Green LED will light and the two
Channel Red LEDs will come on continuously for
approximately 10 seconds then extinguish. If you are within
range of vessels transmitting AIS data the two channels Red
LEDs will flash intermittently indicating reception of a AIS
messages which will be sent as NMEA data via the USB
connection to the computer.

http://www.globemarine.co.uk/wp-cont...USB_manual.pdf

Comprueba los ledes. Si tras apagarse al conectar no parpadean es que no recibes datos. Prueba otra antena. Yo uso la misma de la TV. Va perfecta para el receptor AIS. Si te funciona con la antena de TV pasa del splitter. Es mucho mejor.