In an emergency, an AIS rescue transmitter conforming to the latest standards immediately sends a “MOB distress call” using two parallel signals:
- AIS – GPS position data including course and speed to all vessels within range.
- DSC – Distress call with the current GPS position to previously stored vessels (closed loop), then automatically to all vessels and coastal radio stations (open loop).
This means: An AIS rescue transmitter from Weatherdock ensures that your distress is quickly identified, clearly located, and immediately transmitted to all relevant rescue services – for maximum chances of survival at sea.
Whoever transmits is visible – that’s the whole point of AIS. However, many devices, including the easyTRX3S, have a silent mode: You continue to receive but don’t transmit your own position. This is useful if you want to remain “invisible” in a harbor, for example.
There is no general AIS requirement for recreational craft. However, it may be mandatory in certain sea areas or for those with special equipment.
AIS also increases safety voluntarily – in the North and Baltic Seas, for example, almost all commercial vessels use AIS. With the easyTRX3S, you’ll reliably appear on their screens.
AIS-equipped vessels are displayed with their name, course, speed, MMSI number, and often the destination port.
With a Wi-Fi-enabled transceiver like the easyTRX3S, this data can be displayed directly on the tablet – clearly and intuitively.
Most AIS devices use NMEA 0183 or NMEA 2000 and are therefore compatible with common plotters (Raymarine, Garmin, B&G, Simrad, etc.).
The easyTRX3S also offers integrated Wi-Fi for sending AIS data directly to a tablet or smartphone – for example, for Navionics or iSailor.
The effort depends on the device. Some AIS systems require a lot of cabling (antenna, power, NMEA).
Weatherdock devices like the easyTRX3S are optimized for DIY installation: clear connections, clear instructions, and German-language manufacturer support – no anonymous call center.
- Passive (receiver): You see other vessels while remaining invisible.
- Active (transceiver): You see others and are seen – important for commercial shipping, heavy traffic, or fog.
The easyTRX3S from Weatherdock transmits and receives simultaneously and is easy to configure – even without prior electronics knowledge.
AIS receiver (receive only)
- Price range: approx. € 500,-
- Ideal for: Sailors and motorboaters who only want to see the position of other vessels.
- Advantage: Affordable entry into AIS.
- Disadvantage: You are not visible to other vessels.
AIS transceiver (Class B transceiver)
- Price range: from approx. € 1.200,- (depending on features)
- Advantage: You not only receive, but also transmit your own position – significantly more reliable.
Additional costs
- VHF antenna or antenna splitter (approx. €100–300) → necessary if AIS and the radio are to use the same antenna.
- Plotter integration or NMEA interface (€25–300) → for display on chart plotter or onboard PC.
- Installation/mounting (if not done by yourself, €150–400).
Share an antenna (usually standard on board)
- The AIS transceiver and VHF radio share a VHF antenna.
- This requires an antenna splitter:
- Ensures that both the AIS and radio are securely connected at the same time.
- Automatically prioritizes radio traffic: As soon as you transmit, the AIS is briefly muted to avoid interference.
- Advantage: Only one antenna is required on the mast (optimal for reception range).
Separate antenna for AIS
- You can also install a separate AIS antenna (often on the transom).
- The radio and AIS then operate independently of each other.
- Advantage: No signal loss due to splitters.
- Disadvantage: Additional mounting, antenna height is usually lower → reduced AIS range.
Using an antenna splitter, the VHF antenna can be used for both the AIS transceiver and the VHF radio without any loss of performance.
Yes, each AIS transceiver must be programmed with an individual MMSI number, which must be applied for from the relevant authority.
Yes, AIS targets will be displayed on compatible chartplotters or navigation apps that have AIS reception capabilities.
The device connects to the onboard power supply, the VHF antenna, and optionally to GPS and navigation systems. Many models also offer NMEA 2000 or NMEA 0183 interfaces.
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AIS Class A
- Required for: Commercial shipping (SOLAS vessels, passenger ships, tankers, etc.)
- Features:
- High transmission power (12.5 W)
- Short transmission intervals (every 2–10 seconds, depending on speed/maneuvers)
- Comprehensive data transmission (vessel name, MMSI, position, course, speed, destination port, ETA, navigation status, etc.)
- Purpose: Maximum visibility in maritime traffic
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AIS Class B
- For: Yachts, pleasure craft, smaller commercial vessels
- Features:
- Lower transmission power (2 W)
- Longer transmission intervals (every 30 seconds to 3 minutes)
- Less comprehensive data sets (Based on: MMSI, position, course, speed)
- Purpose: Increased safety and visibility for recreational boating
That depends on your cruising area and intended use. Those who often travel on larger bodies of water, at night, or in poor visibility will benefit enormously from AIS – you can see what’s happening around you and are visible to others.
For starters, the easyTRX3 from Weatherdock is a good option: a compact, reliable AIS receiver, easy to install, and ideal even for smaller boats.
An AIS transceiver increases safety by displaying your position to other vessels. AIS is often required for commercial vessels, but voluntary but recommended for recreational boats.
Depending on the antenna height and conditions, the range is 5–20 nautical miles. Coastal stations or satellite AIS can receive signals over greater distances.
- AIS Transceiver: Transmits and receives AIS data.
- AIS Receiver: Receives only AIS signals and does not transmit its own position.
An AIS transceiver is a device that automatically transmits a vessel’s position, course, and speed while simultaneously receiving AIS data from other vessels. This improves collision avoidance and navigation at sea.
Yes, many devices have a test function that doesn’t send an emergency call. This allows you to check functionality and battery life.
The battery typically has a lifespan of 5–7 years. Replacement should only be performed by an authorized service partner.
AIS MOB devices generally do not require official registration. However, if DSC functionality is used, an MMSI number must be programmed.
Certified AIS MOB transmitters are waterproof (IP68 or higher).
Most AIS MOB transmitters are not self-floating – they require a buoyancy aid or must be attached to a life jacket. The only exception is the easy2-MOB (and its predecessors, the easyONE and easyONE-DSC). All Weatherdock rescue transmitters are self-floating without a buoyancy aid.
The transmission time is usually 24 hours after activation.
Depending on the model, it can be activated manually at the push of a button or automatically when the life jacket is inflated.
Yes, an AIS MOB transmitter works with any AIS-enabled chartplotter or PC software that can display AIS MOB messages. A compatible VHF radio is required for DSC alerts.
The range is approximately 5–10 nautical miles, depending on the antenna height and conditions. AIS signals are received by all nearby vessels with an AIS receiver.
• AIS MOB: Locates the overboard victim via AIS within approximately 5–10 nautical miles.
• PLB (Personal Locator Beacon): Transmits distress signals via satellite (worldwide, longer rescue times).
• EPIRB: For ships, also transmits via satellite, triggers international rescue chains.
An AIS MOB (Man Over Board) rescue beacon is a personal distress signaling device that is activated automatically or manually in the event of a person overboard emergency. It transmits the GPS position via AIS to nearby vessels and—in the DSC version—directly to VHF radios.
Yes, most devices have a test function that checks all functions without triggering an actual emergency call.
