Network setup

The networking is centered around the OpenPlotter node. OpenPlotter software package contain and run multiple services, like NMEA 2000 (CAN bus) interface, I2C sensors, SignalK server etc. It connect to the Raspap router which connect to the internet via wifi ashore or a local 4G router. The other nodes including the laptop connect to OpenPlotter node via wifi. The laptop can connect to both the Openplotter node and SSB node via ssh or VNC, in addition the Openplotter route requests to outside through the Ethernet interface via the Raspap to the internet (if raspap has internet connection). To enable forwarding from the OpenPlotter the forwarding need to be enabled, shown here.

An old Samsung pad is acting as a display for the SignalK web application «instrument panel». Nice to have the data available at all times even when the laptop is closed. A nice recycling of an old pad.

Ideally one would like to run both OpenPlotter and SSB software together on same RPi4, that turned out not to work. Most of the ham radio software was ok, but not the soft modem called VARA. This is piece of Windows software written for x86 systems, and as such need to be emulated on RPi, always a slow and resource demanding task. VARA did not run properly concurrently with OpenPlotter (influxdb, signnalK, etc). Hence, the need for an extra RPi. Maybe newer RPis with more cores is up to it or that VARA is ported to ARM.

Both the OpenPlotter and raspap are on an isolated power supply since they are connected via a cable. The SSB share power (via a 12 to 5V converter) with the Xiegu G90 radio. The SSB node is connected to G90 via a USB audio card and a serial line for CAT control. The G90 is DC isolated from the Aluminium hull, but AC grounded using a bank of 3 kV capacitors. For more on the SSB radio see this page.