AIS and marine electronics
Every vessel on this map is there because it carries a transponder. This page explains the hardware involved — what transmits, what only listens, and what the supporting kit is for.
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AIS transponders & receivers
The hardware that puts a vessel on this map — and lets it see others.
Class B AIS transponder
Transmits your position, MMSI and vessel details to other ships and to shore stations.
Why it matters here: A Class B transponder is what makes a leisure or small commercial vessel appear on a map like this one.
See options on AmazonAIS receiver
Receive-only: shows you nearby AIS traffic without transmitting your own position.
Why it matters here: Receive-only sets are the cheapest way to see AIS traffic, and are what most shore-side hobby stations run.
See options on Amazon
VHF & DSC radios
Marine VHF, handhelds and DSC-capable fixed sets.
Fixed-mount VHF radio with DSC
Digital Selective Calling uses the same MMSI identity as your AIS transponder.
Why it matters here: Your MMSI is a radio identity first — DSC and AIS share it, which is why the number decodes to a flag state.
See options on AmazonHandheld marine VHF
Portable backup radio, typically floating and waterproof.
Why it matters here: A backup radio matters on any vessel relying on electronics for identification and distress calling.
See options on Amazon
Chartplotters & navigation
Plotters, multifunction displays and GPS.
Marine chartplotter
Displays charts, GPS position and — with an AIS input — surrounding traffic.
Why it matters here: Most onboard AIS displays are a chartplotter overlaying AIS targets on the chart.
See options on AmazonNMEA 0183 / 2000 gateway
Bridges instrument data to a tablet or laptop over Wi-Fi.
Why it matters here: A gateway is the usual way to get raw AIS sentences off a boat and into software you can actually inspect.
See options on Amazon
Antennas & splitters
VHF antennas, AIS splitters and the cabling in between.
VHF / AIS antenna splitter
Shares one masthead VHF antenna between the radio and the AIS unit.
Why it matters here: Fitting AIS to a boat that already has one VHF antenna almost always means adding a splitter.
See options on AmazonMarine VHF antenna
Antenna height and quality set your practical AIS and VHF range far more than transmit power does.
Why it matters here: AIS is VHF line-of-sight, so antenna height is the single biggest factor in how far your reports carry.
See options on Amazon
Safety & distress
EPIRBs, PLBs, AIS-SART and man-overboard beacons.
EPIRB
Registered 406 MHz distress beacon for vessel-level emergencies.
Why it matters here: Distinct from AIS: an EPIRB reaches search-and-rescue satellites, not just VHF-range traffic.
See options on AmazonAIS man-overboard beacon
Personal beacon that raises an AIS alert on nearby vessels.
Why it matters here: These transmit on the AIS channels and appear under the reserved 972 MMSI prefix.
See options on AmazonRadar reflector
Passive reflector that improves how you show up on other vessels’ radar.
Why it matters here: AIS and radar fail in different ways, so a vessel carrying AIS still wants to be radar-visible.
See options on Amazon
Books & reference
Seamanship, navigation and radio-licence study material.
Navigation and seamanship reference
Standard reference texts on navigation, collision regulations and seamanship.
Why it matters here: AIS is an aid, not a substitute for knowing the collision regulations.
See options on Amazon
A note on how these links work
These point at Amazon search results, not at one hand-picked product. We are not in a position to bench-test marine electronics, and pretending otherwise would be worth less to you than pointing at the category and letting you read the listings. Buying decisions on safety equipment should rest on the manufacturer's certification and your own requirements, not on a link from a tracking site.