Nauticast B AIS-300 AIS Class B Transponder

The reliable and sturdy predecessor of our current Nauticast B2







Product discontinued


The B300 was sold worldwide as a consumer market class B device and is still in operation many, many times. Until today it fulfills all relevant class B specifications and norms. 

We offer the following service and repair options:

  • MMSI reset: If you purchase a boat with our B AIS-300 installed, or buy a used device, you may need to set a new MMSI number. Regulations in most countries require that this be done by the manufacturer or an authorized dealer. We offer this MMSI reset remotely via Internet by one of our service technicians. All you need is the B AIS-300 connected to a PC with internet access via the data cable. Alternatively, you can contact a local partner company in your region. Please refer to our partner network listings.
  • Repair / Updates: If you experience problems or require assistance please contact us at support@nauticast.com or use our contact form


Technical Specifications 

Model Nauticast B AIS-300 


7.8 x 6.22 x 1.84 in. (198 x 158 x 46.7 mm)


13.2 oz (375g) 


9.6-15.6 VDC
Average power consumption 4W 
Peak current rating 2A 


RS232 38.4kBaud bi-directional
RS422 NMEA 38.4kBaud bi-directional


IEC 60945
IEC 62287, Section 5, Cat c) exposed to the weather
-25ºC to +55ºC 


Transmitter x 1
Receiver x 2 (One receiver time shared between AIS and DSC)
Frequency: 156.025 to 162.025 MHz in 25 kHz steps  


GPS Receiver (AIS Internal)  IEC 61108-1 compliant


Power, TX timeout, status, pre-set SRM sent

Operator Controls:

Optional pre-set safety related message (SRM) transmit button



Upgrade Options to Nauticast A2!

Switching from Nauticast AIS, ACR X-Pack, Saab R4, Oceansat or L3 Inland to the Nauticast A2, while leaving most of the current installation like connection box and data connections in place. For Details see

Nauticast B2 with USCG and FCC certification

With its US Coast Guard and FCC certification the Nauticast B2 is eligible for US vessels, where class B devices may be used to fulfill AIS carriage. Read more ..

AIS Training via Skype

Nauticast now offers AIS training in several modules via Skype. All you need is a PC with internet connection, microphone and speakers. The 3 standard modules are: General AIS/Nauticast A2 Installation and Operation/Nauticast AIS Repairs. Please contact Technical Support if you are interested.

Nauticast A2 approved according to ITU-R M. 1371-5 and CCNR Test Standard 2.0

With the latest round of certifications the Nauticast A2 complies with the most current SOLAS and Inland regulations. Read more ..