Own vessel shows up in AIS targets list

I have a Raymarine AXIOM chartplotter, with Raymarine AIS700 AIS transciever. I recently replaced the NMEA wifi gateway on the boat.

Now, my own vessel is listed as an AIS target in Coastal Explorer.

The AIS700 is the only ais device on the boat.

Any ideas on where to start troubleshooting this issue?

Pretty sure that before I replaced the NMEA-wifi gateway my own vessel was not being listed as an AIS target in CE.

The gateway is a Quark A034. The prior (now failed) device was a Yacht Devices YDWG-02.

Given that the problem did not start until I replaced the prior gateway device which had failed, I am suspecting some configuration issue in the A034.

But, thought I’d check here to see if there was some Coast Explorer configuration issue I inadvertently messed up.

The Quark support forum has a discussion of this issue for OpenCPN, and provides instructions for entering your own ship MMSI into the software so that will be ignored.


Hello Robert,

Normally, you would never see your own-ship. AIS transponders send information about your own vessel using a different message from other targets. I’ve seen this sort of thing happen when a system is connected to two AIS’ at the same time, such as having a VHF radio that also acts as an AIS receiver. If there’s something like this going on, you might see your own vessel since the other AIS won’t know it’s not very near another target. You’d be in a permanent state of collision warning with yourself.

Do you by chance have another AIS system connected up to the Nemo? I’ve not come across that Gateway yet, so it’s also possible that it’s involved somehow.

The only AIS system is the Raymarine AIS700 attached to the boat;s NMEA2k network. I do not have a second AIS receiver or combo radio/ais receiver

“You’d be in a permanent state of collision warning with yourself.” – Exactly.

The Quark A034 is the only gateway device on the boat.

Looking at your Quark A034, are you getting NMEA 2000 data that’s been converted to NMEA 0183?

I’m not at the boat, and I have not done the deep dive into the A034’s configuration

In terms of physical network connections - The Quark is only connected to the boat’s NMEA2k network. As is the AIS700.

Is your computer connected to it over Ethernet or WiFI? If it is, then it can only be that it’s translating NMEA 2000 to NMEA 0183, since there is not standard for transmitting NMEA 2000 over a network.

If it is translating, then it’s almost certainly not generating VDO sentences, but sending VDM for other vessels and your own ship. If so, I’m not surprised. This translation is difficult and fraught with peril, meaning we’ve seen similar mistranslations for AIS before.

The laptop running CE is attached to the NMEA2k network via wifi.

Then you aren’t receiving NMEA 2000 from Coastal Explorer’s perspective. As before, there is not a standardized method for doing that, only proprietary methods. There is a standard being developed, called OneNet, but it’s still being worked on.

In any case, if you look at the details of the port that we’re receiving data on, I expect you’ll see NMEA 0183 sentences, and that there will be lots of !AIVDM, and either very view or no !AIVDO sentences coming in.

If you aren’t sure about how to check the port so you can see the incoming data, it might be faster if you give me a call.


I tried filtering the own ship ais message (AIVDO) on the Quark A034 device - that did not solve the problem. I could see that no AIVDO messages were being received, but I kept getting collisions alarms with myself.

I swapped out the Quark A034 with a Yacht Devices YDWG-02 and everything just works like it is supposed to. I can see both AIVDM and AIVDO messages being received, but I am no longer getting collision warnings with myself.

I’ve emailed Quark tech support. But, for now I am really liking the Yacht Devices YDWG-02 NMEA to WIFI device. It just flat works.

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I am getting the same issue, sort of, Coastal Explorer is warning me of a collision with my own boat ! repeats during voyage, I have not found the source, but thinking something has a TX sentence on my NMEA 2000 network or something tied to my NEMO gateway as and 0183 coded message: could include

  • AMEC WideLink B600S Class B SOTDMA AIS Transponder with Integrated Splitter
  • VHF RADIO IC-M506 with AIS

In your case, it’s probably your VHF radio sending us VDMs for your vessel, since it would be receiving the broadcasts from your AMEC transponder. I would check your IC-M506 to see if it has a feature allowing you to enter the MMSI number set in your transponder, telling it not to pass on VDM sentences for that MMSI.

Can you turn of the AIS output from the M506? I’d guess that is your issue.

The AMEC AIS transponder should be providing all the AIS data you need, so that the M506 is not adding anything to your situational awareness.

We have the same problem on the Columbia River, but it happens because AIS signals are repeated on shore for the whole river. When underway, the ghost ship is behind us due to system delay. I so far have been unable to block our mmsi. (XB800, Rarmarine Axiom plotters on NMEA2k buss).
Craig, s /v Sequoia, Outbound 44 #5

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There is a feature request in our feature request tracking system to provide a way to filter out own-ship’s MMSI, so this may be added in a future update.