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Random AIS safety message


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We keep getting this message at seemingly random times - sometimes at anchor, sometimes underway. Its getting quite annoying to say the least.

Our system is a Vesper XB000 and the screenshot is the message on a Raymarine Axiom MFD.

Anyone know why we are getting it and how to stop it? I emailed Vesper and they want to know the light sequence on the XB8000 LEDs so I will have to wait for the message to appear again before I go back to them.

"The position not available" aspect of it makes me wonder if the GPS fix is lost - but even so I shouldn't be spammed with these messages?

20211227_121138.jpg

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That makes sense. I presume it's probably the AIS (Vesper) GPS?

It's very intermittent, like once every 4 hours, so may need to do a NMEA recording to see what's happening.

Atenna is on radar arch and been good for ages.

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I have ordered a new GPS antenna.

In the meantime I have checked quality of the GPS fix on my chart plotter against Vesper GPS. 

Chartplotter gets about 12 satellites with differential fix.

Vesper gets about 7-8 - is that the db down the left (y) axis?

Does anyone else have a Vesper and can send me a screen shot of the normal fix quality?

Cheers

 

697595942_vesperstatus.png.b1929e0434ff8fec0995387ddf12e3af.png227481150_veserstatus2.jpg.be675400619edcbfeb223473cae96d0c.jpg

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PS: I was watching the HDOP during one of these position lost messages - the HDOP never changed from 1.42 - which is pretty acceptable horozontal fix quality.

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I too get it mainly at Motuihe but also off the back of Waiheke. Other people have reported it on B&G gear with Vesper.

I using Navionics for my charts.

Havent seen anything in the AIS standard which would allow conditional display of messages, i.e. if boat is in position X and speed is grater than Y then alert.

Would love to know MMSI of who is sending it - maybe a program where you can log AIS traffic for debugging?

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Spoke to the Harbour Master - they are not broadcasting these messages. I think its something to do with Vesper or maybe Navionics chart cards?

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Speaking of strange messages 

I keep getting one or two targets showing in my target list of boats that are thousands of miles away, up to 8000nm

They are in range or I’d not pick them up, so either they are transmitting an incorrect position or my raymarine system is receiving it incorrectly 

anyone else with this issue ?

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Yesterday I too received the ASI  5knot zone message, 2/3rds of the way from Barrier to Kawau. 

It came up with an MMSI of 51220022, which when I search on the RSM callsign register there is no such record.

On top of that, the MMSI is not showing up as a vessel on my AIS vessel list ( see picture " Message was received from an unknown vessel")

 

Might also be worth noting, I do not transmit AIS, just have a receiver. 

20220106_165416.jpg

20220106_165403.jpg

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Good job getting the MMSI - its was on my todo list to get that (Raymarine doesn't seem to make it easily accessible for Safety Messages).

I will report it to RSM see what they can find out - starting to suspect it might be prank. Even the pattern of numbers in the MMSI seem a bit too "made up"

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MMSI starting in 5 denotes a vessel (not a shore station) registered either in NZ or another nearby country in Oceania.

I believe within that "number space" 512 is allocated to NZ so any number starting with 512 would be nz registered and they are allocated starting from 1 so this would be the 2022nd vessel to register an MMSI in NZ. Seems like a plausible real MMSI.

Or could be a made up or spoofed MMSI, but if someone just picked a random number then the chances are that it wouldn't start with 512 unless they really knew their stuff. If they knew their stuff well enough to use the right MMSI code then they'd probably choose to impersonate a shore station rather than a vessel.

Considering they didn't provide a vessel name, it's dodgy on some level. Self-appointed speed police? It's not the real police, Deodar is 512000369 so she was registered earlier...

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