em-trak B921 Class B AIS Transceiver - 2W CSTDMA

The em-trak B921 Class B AIS Transceiver - 2W CSTDMA is a compact maritime safety device engineered for vessel operators, commercial fishing crews, and professional maritime teams who require reliable vessel tracking and collision avoidance on the water. This Class B AIS transceiver broadcasts your vessel's position, course, and speed to nearby vessels and shore-based monitoring stations, enabling critical situational awareness in congested waterways, open ocean operations, and emergency scenarios. Weighing just 1.55 pounds with a footprint of 7 x 6 x 8 inches, the B921 delivers essential AIS capability without burdening deck space or power budgets aboard smaller vessels and commercial craft.

The 2-watt CSTDMA (Carrier Sense Time Division Multiple Access) transmission protocol ensures efficient spectrum sharing and reliable message delivery across international maritime frequencies. This transceiver autonomously manages transmission timing to avoid signal collisions, a critical function in high-traffic shipping lanes and port approaches where multiple vessels transmit simultaneously. The Class B designation indicates compliance with international maritime standards while providing proven performance in tactical and civilian maritime environments; 2-watt output penetrates coastal clutter and effectively reaches receiving stations at operational distances. Integration with standard maritime VHF systems allows dual-channel monitoring, enabling operators to maintain both AIS tracking and voice communications without platform conflicts.

This transceiver serves commercial fishing operations, harbor patrol, military coastal operations, and professional rescue teams requiring persistent vessel identification and automated distress capability. Installation requires standard 12-24 VDC marine power and connection to an external VHF antenna; dual-channel capability allows simultaneous AIS transmission and voice radio operation. Maritime operators with existing VHF systems integrate the B921 seamlessly into established communication architecture, gaining automatic position reporting without manual intervention. Regulatory compliance for international waters and U.S. coastal zones is built into firmware, eliminating configuration complexity and ensuring legal operation across jurisdictions.