B & G NAIS 400 Class B Transponder
Reviewed Jun 2016
We had the B & G NAIS 400 class B AIS transponder installed on our 12 metre catamaran in Townsville at the end of our cruising season in October 2015 just prior to returning home. The unit was part of a full overhaul of our boat electronics in which we upgraded the majority of our electronics to Simrad and B @ G gear. The unit since installation was connected to our VHF aerial via a spliiter which is a very acceptable manner rather than install a seperate VHF antenna with the AIS informatioin being displayed on our 9 "Simrad" Multi Function Display via a NMEA 2000 connection between the AIS unit and chart plotter.
As I had not completed the VHF radio operators course at the time we could see other craft with AIS transmitting capabilities but we were not transmitting our position. To be able to transmit your positin via AIS you must have succesfully completed the course to obtain VHF/ Short Range Operator Certificate of Proficiency (SROCP) . Once you have your certificate you can apply for an which MMSI number through the Australian
Maritime Safety Authority (AMSA) which is a unique number given to your boat. The MMSI number on being obtained is then entered into the NAIS 400 unit via the use of computer program (supplied with the unit on a CD) Also entered are you and your boat details including on shore contact numbers. Once these details have been entered correctly you are capable of transmitting details such as speed, course, boat details etc.
The AIS is a valuable safety tool which enables you to veiw commercial and recreatioinal craft (who have AIS installed and operating) not only in close proximity but large distances which is only restricted by the height of your antenna and the antenna on othe craft. When crossing busy commercial shipping lanes or entering busy harbours targets are normally identified by a triangle on the chartpotter display. An alarm can be set to alert you of boats on a collision course with you. By highlighting the triangle the target details are shown on the display advising course over ground, speed over ground the vesells details. For those cruising, the AIS regardless of brand allows family and friends to monitor your progress. Transmissions can be turned off if required if a switch is connected to the unit by the technician or by turning off the unit completely.
We are more than happy with the B and G NAIS 400 and can highly recomend the unit. Recommended retails price seems to be around $899 and splitters vary in price from upwards of $220. Installation can be done by a competent handyperson but a technician is well worth the money to get to the installation and programming.