Onwa KS200A SART AIS ‘Black Box’ Class B+ AIS

Last one


Class B+ AIS with SOTDMA technology  5 Watt transmit power and provides an emergency SART function as well.

24 month UK warranty.

This product communicates with other equipoment via NMEA1083, however, if you need NMEA2000 an Onwa NMEA0183 to NMEA2000 bi-directional converter will do this for you and also add wi-fi to your system as a bonus.

Perfect for use as a stand alone transmitter/receiver to send your AIS details out to all AIS equipped vessels within range.  Can easily be linked by the data cable provided to an existing any make plotter so that all AIS vessels in range can be overlaid onto the chart page of your plotter. If you have an Onwa non-AIS plotter, this already has an AIS ‘radar’ page built in together with CPA* and TCPA* alarms that can be user set – this is a very valuable safety feature.

*CPA = closest point of approach  *TCPA = time to closes point of approach

There are two versions
KS200A, this is the box of tricks that receives AIS transmissions from other vessels giving you their COG, SOG, Position and MMSI etc details. At the same time it will be sending your same information to all other AIS equipped boats within range. It is a completely self contained unit and just needs power, GPS and AIS antennas to function.

KS200A SART, this is the same device but with the addition of a button on the unit that when pressed will send out a distress message to all AIS vessels within range. This posting refers to this version.

Note…..KA200A SART is not an EPIRB.   An Emergency Position Indicating Radio Beacon is used to alert search and rescue services in the event of an emergency. It does this by transmitting a digital message via the multinational Cospas Sarsat network. The KS200A doesn’t do that, instead it transmits the distress call via the AIS RF signal frequencies. Not so good you may say – and, yes, in that you will be right; but, the AIS distress signal will be picked up by all AIS receivers within range meaning that a vessel close by can come to your aid possibly very much faster than the Rescue Services can do as they have to wait on your call via the satellite system and then get to you from, maybe, some miles distance. If your wallet can support it then ideally both devices will be the way to go but either way, that other vessel just a short distance away is still best able to offer help in the shortest possible time. Think ‘Titanic’ ……….. in the 2 hours and 40 minutes that it took for the Titanic to sink another vessel was within sight but couldn’t be contacted.

AIS equipped vessels are shown overlaid onto your chart

Vessels on the River Thames near Tilbury using Onwa K-chart2. The curser has been placed over one and as a result its details can be seen



AIS ‘Radar’ screen showing an alarm alert as seen on an Onwa plotter, even one without its own AIS built in. Note: Other make plotters may not present this information as clearly if they lack the built in AIS Radar screen feature that exists in every model Onwa plotter.

AIS ‘radar screen with alarm active – the red boxes are normally empty until an alarm is triggered, they then show details of the vessel that is on a collision course. The vessel also shows as red on the ‘radar’ screen

GPS Aerial/antenna: KS200A and AS models, as shipped, do not come with any aerials. You will need both a GPS and an AIS type aerial for this unit to function.

AIS transceivers must have their own GPS aerial and it is imperative that the GPS signal is strong and constant. Loss of GPS will mean that the system will not know where your boat is relative to other vessels and the AIS collision alarms will cease to function and other vessels will only see your last good transmission. We strongly recommend an external aerial with the Black Boxes as not having a screen to monitor the satellite signal there is no way to check the validity of the GPS signal. There is an option to buy an external (‘mushroom’) type with a surface mount base in the buy options and also the option to buy a Glomex model RA111AIS aerial complete with 10 metres of very low loss RG8X cable terminated at both ends with PL259 connectors. Note; if you need a different custom made cable length with either one or both PL259s connected please message or call. (having one end only terminated greatly assists installation if the cable is to be passed though a confined space or hole. 

Programming the KS200A with a vessel’s AIS details:

AIS details (MMSI etc) must be set into both the KS200A and 200A/SART

Setting up the KS200A with your vessels’ AIS details (MMSI, name etc) requires some technical knowledge and additional hardware in the form of an NMEA/Serial to USB interface is required. We do this for you at no cost before dispatch. Should you ever change your boat – no problem, just return the 200A and we will amend your boat details to match the new boat. No cost apart from return postage.

  • Compliance:
  • Class B+ SO-TDMA AIS ‘Black Boxes’ built for the UK market comply to E.U CE legislation and have Radio Equipment Directive certification (RED), this is available on request.
  • Warranty:
  • Warranty on this product is 24 months  (return to UK base)

 Note that KS200A devices available on the internet that are built for use outside of the E.U and UK may not conform to compliance requirements and be illegal to use in UK and EU waters. Further, ‘Grey Imports’ are not supported by Onwa in the UK and must be returned to the supplier in the event of a warranty claim.

error: copyright 2023