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Hi @Sparohok, thank you.

This is definitely unusual, Saillogger normally eliminates all those starting points automatically and works without any issues. You’re clearly observing something different.
Having a position all the time is actually a good thing, so that won’t cause the issue, but I suspect it has something to do with that USB GPS.

I presume you have a GPS source on your NMEA network (chartplotter, AIS, etc.) that comes online before you start moving. If so, can you configure a priority so that your USB GPS is always the lowest priority and only used when nothing else is available?

Go to Signal K → Server → Data Connections and, using the Priorities table at the bottom, configure priority for your navigation.position and give higher priority to NMEA sources (make sure your instruments are on while you do this). Put the USB GPS at the bottom, and set a timeout of 5 or 10 seconds.

It will look something like this:

Screenshot 2025-08-13 at 9.00.35 PM.png

Make sure you restart Signal K afterwards and let us know what happens on your next trip.

Hi @admin , just saw this thread and I have a suggestion. I recently wrote an algorithm to simplify GPS tracks which worked really nicely. I'm not sure if it's original but worked for me. Basically use Shoelace formula (https://en.wikipedia.org/wiki/Shoelace_formula) on a sequence of waypoints. If the area of the polygon formed by those waypoints is less than a threshold, add another waypoint to the sequence; if it's more than a threshold, turn it into a track segment and start over again with the next 3 waypoints. That way the area threshold is a single number that users can tweak for their desired level of detail, you don't have to explain a bunch of parameters. Points all in a line have low area, but the momemnt there's a turn the area increases a lot. Happy to share my Python code.

Hello John, That’s a good catch, I’m not the developer but I’m assuming that that was the most intuitive direction when he developed it. I’m guessing he’ll comment on this if need be. Thanks, Kevin.

@admin

Thank you for the magic. I have now activated the Windy reporting option and will monitor the data on Windy to confirm all is as expected.

Cheers, Bill on SV Denali Rose

Thanks for hoping on it and deploying a fix so quickly. Behavior looks correct now. 😉

Thanks! Will do that.

Thank you very much. Sadly we moved since Saillogger went down and I updated it. The .GPX track was to fill in our transit from when it went down and our new location where I brought it back up. Not the end of the world. Glad to have our beloved Saillogger back up and running!

I second @MacJL
There is already a nice autostate plugin.
No need to reinvent the wheel.

Glad to hear you sorted it out! For future reference, it may take up to an hour for new data keys to show up in Saillogger. This is only applicable for the initial configuration, once done data flows in regular one minute intervals.

@admin Thank you for the work!!!

This was resolved in a different thread. Upgrading to the latest Victron firmware and installing Saillogger plugin 4.2.1 or later will work.

Hmm, spotty access point should not cause this. It is almost always due to GPS. Please keep monitoring and let us know if you observe anything else that is unusual.

@jonnys , we have been investigating this and it turns out this is an issue in the latest version of VenusOS v3.62, please see the following post for details and potential workarounds:

Link Preview Image FIXED: Saillogger plugin fails to install on Venus OS v3.62

IMPORTANT NOTE: This issue has been resolved in Saillogger Signal K plugin version 4.2.1. In collaboration with Victron, we identified the root cause and fix...

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Saillogger Community (community.saillogger.com)

Thank you for sharing this Alastair.

It looks correct, we plan for more improvements for this logbook, so stay tuned.

Ok, please try two things:

Check the interface name on Signal K for the CAN interface, if it is can0 or vecan0, please try vecan1. Make sure to restart it after you make a change. See if you can connect it to first port (even temporarily) and if it makes any difference.

Independently, the first port is galvanically isolated, the second one is not. For NMEA connection, Victron's strong recommendation is to use the first port.

Is Victron GX connected to NMEA 2000? You need a special cable for that (you could also make your own, see this article)

If you verified the connection, make sure your GPS source is turned on (it might be the chartplotter).

When everything is working you should be able to go to Signal K Data Browser and search for navigation.position and it should show your current position.

If you haven't already, do check this tutorial, it explains though: