So ... my setup:

Two RPi ... one has "Moitessier" hat  and is my GPS, Mag Heading and AIS source ...

The other has my OpenCPN screen and a "PiCan M" NMEA 2000 interface. Depth, speed and wind information comes up the NMEA 2000 interface. This is my "main data server"

The both run SignalK andI have a nice setup where one feeds the other.  All data from the "Moitessier" server ends up in the "main" server along with the data coming up the NMEA2000 buss ... and my OpenCPN application connects to this "SignalK" source as its only data source and everything is there, including AIS data on other vessels.

I cannot see any (AI)VDM data in the data browser, but, I guess the data is ephemeral so "passes through" SignalK but does not create nodes?

Anyway,  I get good AIS data on my OpenCPN screen and as SignalK is the only datasource to this, it must bee in there somewhere.

I have configured the 'signalk/UDP-nmea0183-sender" plugin, set the broadcast address and the port, ticked the two events. I configured Navionics to listen for this port.

I configured the "Convert SignalK to NMEA0183" plugin to convert the SignalK "DBT" value (depth below transducer) and this works .. I can see the messages going out  and they arrive on Navionics, I now get the depths displayed on screen on my tablet in Navionics, so this data connection is working.

It comes up as a "DigitalYacht WLN10" device in the "paired devices", which seems correct.

I do not get any AIS data.  I cannot see any AIS data events going out, there is no "VDM" or "AIVDM" option in the "Convert SignalK to NMEA0183" plugin.

How can I pass AIS data out to my Navionics tablet?