Shipxplorer USB dongle

[Richard Montgomery]

Hello

I have a shipxplorer usb dongle that I would like to use with Kplex.

https://www.shipxplorer.com/ais-dongle

In plugging in the device it creates /dev/swradio0

Can Kplex talk directly to this usb device and what settings should I use if it does

filename=/dev/swradio0
direction=in
baud=38400

Thanks

Richard

KB4YTM

[Keith Young]

There doesn't seem to be much data on the site...I guess they just want you to use their software?  But I'm guessing the above should work as long as it transmits in NMEA-0183 format it should be fine.  You probably don't need "baud" for a device like this: it probably won't be settable.  If it doesn't work try "strict=no".  And if that doesn't work try od -c < /dev/swradio0.  If you're not doing this as root you might want to check the permissions on the device and add yourself into any required group.

[Richard Montgomery]

Thanks Keith

Trying  od -c < /dev/swradio0 shows a continuous stream of data like this:

3304660 204 203   y 210   {   { 201   z 200   {   {   y   ~ 210   ~ 206
3304700 203   z 177 204   z   v 206 202 200 204 207 201 201   t 203 200
3304720   | 203 200   { 206 177   | 200 177 177   }   y 206   z 211 214
3304740 201   } 177 210   { 202   s   v 210   ~   ~   x   y 205 205   v
3304760   u 202   { 206   ~   {   r 202 205   z 200   ~   ~ 207 204   {
3305000   v   v   ~   z 205   x 202   | 204   y   t 177   z 203 207   |
3305020 200 206 206 203   } 201 202 212 211 205   ~ 201 177   y 204 211
3305040 205 202 201   } 222   { 205 210   z 203 201 206 206   z   {   ~
3305060   w 203 204 201   |   ~   y 207 202 177   } 220 204   ~   ~   v
3305100 204 214 200 201   } 204 204 206 207 206 203   u 206   v   {   v
3305120 202   y 205 207   | 203 206 201 202 207 203   } 204 203 201   x
3305140 203   y   w 177 201   z   {   u 201   y   |   v 204   | 203 203
3305160 200 177   { 200 177   { 210   z 205 213   |   v 204   z 212   }
3305200   w   y   x 210 205   { 202 200 203 206 206   x 201   w   { 206
3305220 205   x 214   u 214   x 205   { 177   { 201   {   | 203   | 200
3305240 202 203   {   q   x 177 205   t 206 206   |   ~ 214   s   |   |
3305260 177   y 213   {   { 207   y 207   | 205 201 201 215   | 211 177
3305300   |   v 207   r   ~ 202   | 204 215 200 211   v 204 200   {   {
3305320 202   j   } 203 202 210   |   y   | 204 213 201 207 201 207   {
3305340   |   ~ 205 202   u 202   w 207 211 177 205   z   z 202   {   t
3305360   { 210   | 205   { 200 202 203 202 210   y   ~ 177   }   | 207
3305400   z 201   ~ 204   ~   x 200   { 212 202   y   { 205 210 212   |
3305420 201 203   ~ 206 200   }   v   ~   y 205 212 177   { 203   u 211
3305440 200   z 203   w 204 204 200   ~   | 177   z 205 202   x   y 203
3305460   k 214 202 177 200   | 202 177 204   | 214   ~ 207 211 213 177

Not sure what to do with this info

Thanks

Richard

[Richard Montgomery]

By the way I'm using AIS-catcher software and it does decode using this USB dongle

https://github.com/jvde-github/AIS-catcher

I install AIS-catcher via this script:

https://github.com/abcd567a/install-aiscatcher

All my other sites are using Kplex but with the Daisy HAT AIS receiver board

Thanks

Richard

[Keith Young]

This is presumably an str dongle, in which case no kplex doesn't decode that but can take output from programs which do (aiscatcher, rtl-sdr...). The script you reference above for starting aiscatcher shows it broadcasting output on port 10110 on the loopback interface (127.0.0.1).  You could add an interface to kplex to capture that:

[udp]

name=shipxplorer

address=127.0.0.1

direction=in

port=10110

"port" is unnecessary given 10110 is the default but you might want to change that to something else in the aiscatcher startup and kplex config to simplify other configuration.

A little googling found someone who seems to be using rte-sdr to do something similar with a different-but-apparently-functionally-similar dongle:

https://www.klofas.com/blog/2021/ais-decoding-with-rtl-sdr-dongle/