AIS CLASS B TRANSPODER CHART PLOTTERS

The other cat5egory of AIS is more suitable for smaller vessels and leisure craft. They are simplified and can combine charts and maps with the GPS display, and incoming AIS data to produce a pictorial view of the local area. Normally their data is sent in packets separated by 30 seconds or so, but this is perfectly acceptable for smaller and more agile vessels, even in crowded waterways. The main difference between all the available units is the size of the screen and the extra features they have - making appropriate selection something that is mainly down to the features, and what advantage they have for the user. There are small differences in how the data is presented between the commercial Class AIS and the small vessel system. The commercial sets will include details about the vessel, it's destination and type so a tanker is clearly different to a cruise liner. With class B, the normal requirements to be included in the broadcast data will be MMSI number, callsign, boat name and it's type. Some can also give details of length and beam. These need to be programmed in. Like all devices that transmit, an AIS transponder on your boat requires adding to your OFCOM radio licence. They also offer fishermen the facility to tag nets with an AIS buoy and it's location will appear on the display. As with car SatNavs, the mapping can be selected from a number of paid sources and some free sources, depending on the level of detail you require. They normally are supplied with a GPS antenna that needs to be fitted but also need a separate VHF antenna, or splitter network to enable reception and transmission of data. This has an impact on range, so various types can be connected. Keep in mind that commercial vessel systems involve high power and taller antenna locations so their range is greater -  for a small vessel Class B system, 7 to 10NM would be typical. Collision avoidance is one common requirement for boat operators decision to purchase and install AIS, but leisure users who often go to see in small groups find knowing the realtive positions of the other vessels in a group very useful.

Size and features

The two AIS transmponders above are broadly similar in features but one has a 4.3" colour display and the other has a larger 7" display. Click on the images for more information.

When you purchase an AIS transponder from us we are happy to do your initial programming for you.