Why doesn't my AIS position update on marinetraffic.com?

Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Looks like none of the Class B AIS targets on Great Salt Pond have been seen in quite a few hours. It's not just you. Its probably just that their receiver in the area is offline for now.
Most of the partner AIS statons are marinas with little or no IT infrastructure. They are not used to keeping systems up 24x7. Someone unplugs a router and no one knows until Monday morning.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,876
CAL 35 Cruiser #21 moored EVERETT WA
getting your data up and into the cloud.
This is true, but really it is the opposite. Once you register for the service, you input your boat data into their database. So your data is "in the cloud" so to speak.
I have not investigated the "satellite remote feature", as the cost and the lack of need were stoppers.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,876
CAL 35 Cruiser #21 moored EVERETT WA
What is the VSWR reading?

VSWR stands for Voltage Standing Wave Ratio and is a measure of the how well matched a transmission line (e.g. your antenna cable connected to the VHF output of your WatchMate) is to its termination impedance (e.g. your antenna). VSWR can be thought of as a comparative measure of how much power, generated from your WatchMate or XB Transponder, is delivered to the antenna and how much of it is reflected back and lost in the poorly matched transmission line. You care about this as it will effect your transmission performance. A high VSWR will reduce your effective transmission range and can also lead to other problems. If your WatchMate is reporting a problem with your antenna connection or high VSWR, please look at the previous FAQ for troubleshooting.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,876
CAL 35 Cruiser #21 moored EVERETT WA
You did not by accident switch the AIS system into "silent"?
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
This is true, but really it is the opposite. Once you register for the service, you input your boat data into their database. So your data is "in the cloud" so to speak.
I have not investigated the "satellite remote feature", as the cost and the lack of need were stoppers.
I don’t think that’s true.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,876
CAL 35 Cruiser #21 moored EVERETT WA
Without an internet connection (the Cloud connection) you will not be able to see the VesselFinder app/service.
 
May 20, 2016
3,015
Catalina 36 MK1 94 Everett, WA
I agree with @Jackdaw - it’s probably the shore receiver - to be listed in any of these systems one of two things needs to happen 1) a shore receiving station needs to be running special software that updates a global database somewhere on the internet or 2) an individual boat with an internet connection, and running the vendors app can update the data - regardless of whether they transmit On VHF or not. Big boats way out to sea use a satellite internet connection to do this. Note: people in this latter category who are not transmitting data will NOT show up on chart-plotters, it’s false feeling of safety!!!!

Get far enough away from a shore station, your probably invisible. This is why I have a Delores/Garmin InReach - I push my position every 10 seconds and can send predefined text messages. My wife gets them when I up anchor, drop the hook or decide on a weather delay. I pay more each month for the service than I did for the InReach.

Les
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,876
CAL 35 Cruiser #21 moored EVERETT WA
Sorry I am not at my boat so I cannot see my configuration. Your's does look "Good".
On tab one there is a "smoothing" feature. Try unblocking that. It is designed to provide quicker transmission of signal using fewer satellites so that when you are traveling above 48 mph you can still be seen.

Last suggestion is to turn the AIS off then bring it back on. That should initiate your system and re-register your position in the "Cloud".
 
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jviss

.
Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
Get far enough away from a shore station, your probably invisible.
Les, that is total B.S.! You don't understand how AIS works. If you are within VHF range of a vessel with AIS, receiver-only or otherwise, you will be seen. It operates on VHF frequencies 161.975 Mhz and 162.025 Mhz - 87 & 88 old VHF channels. You don't need a shore station to be seen by other vessels that are within VHF range; and, vessels you can see on the Internet will not show up on your chart plotter! The shore station is only to put the data on the Internet.
 

jviss

.
Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
Note: people in this latter category who are not transmitting data will NOT show up on chart-plotters, it’s false feeling of safety!!!!
Assuming you are referring to "Big boats way out to sea use a satellite internet connection to do this." This is baloney, too. If they are running AIS, which they are required to, by law, and you are within VHF range, they will show up on your chart plotter.
 
May 17, 2004
5,565
Beneteau Oceanis 37 Havre de Grace
I think what Les is trying to say is that your boat's position can be reported on this kind of site in either of 2 ways - App or satellite to a tracking service, or AIS over VHF. AIS over VHF will only work if you're within range of one of their internet connected AIS receivers. Outside of that and yes other ships will still see you, but you won't be visible to MarineTraffic or any other website.
 
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jviss

.
Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
I think what Les is trying to say is that your boat's position can be reported on this kind of site in either of 2 ways - App or satellite to a tracking service, or AIS over VHF. AIS over VHF will only work if you're within range of one of their internet connected AIS receivers. Outside of that and yes other ships will still see you, but you won't be visible to MarineTraffic or any other website.
Yes, I agree. If that's what Les meant, fine, but that's not how it came across to me, especially "Note: people in this latter category who are not transmitting data will NOT show up on chart-plotters, it’s false feeling of safety!!!!"
 
May 17, 2004
5,565
Beneteau Oceanis 37 Havre de Grace
Assuming you are referring to "Big boats way out to sea use a satellite internet connection to do this." This is baloney, too. If they are running AIS, which they are required to, by law, and you are within VHF range, they will show up on your chart plotter.
If you are broadcasting AIS via VHF then yes that should see you. But if you're only using an internet connected app to report your location on the internet, then no, other ships won't see you.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,876
CAL 35 Cruiser #21 moored EVERETT WA
jviss, Using your boat name I see it on Marine Traffic.
https://www.marinetraffic.com/en/da...ksearch=sagittarius&flag_in|in|USA|flag_in=US

When searching in Vessel Finder your boat does not appear in a search.

You are about 9nm from the last reporting station which located you in the "GreatSaltPond". You could be at the fringe of reception for the Marine Traffic system.

You are correct in my understanding that Class A traffic that sees your signal can update the AIS system with your location. But it is more likely that your update will occur via a land based link.

Checking on Vessel Finder, note that your distance from one of their land based posts is more than the 9nm. this may be why you are not seen on that AIS source. See attached map.
 

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jviss

.
Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
Thank you. Yea, I was on marinetraffic.com after anchoring here, now I'm invisible. Curious.
 

jviss

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Feb 5, 2004
7,089
Tartan 3800 20 Westport, MA
O.K., fog starting to break up here, and wind calming down a bit, ate lunch on board, time to go ashore!