MultiTech Conduit - How to enable the inbuilt GPS


(Helioz) #1

After following the instructions provided here my gateway was operational.

However, upon checking /var/config/lora/local_config.json I noticed "gps": false, is switching the GPS off.
The log file (/var/log/lora-pkt-fwd.log) shows

#GPS DISABLED

Whilst this doesn’t cause any issues with packet forwarding, it will affect the availability of accurate time which is required to calculate Time Difference of Arrival (TDoA) which delivers end-node location information in conjunction with a v2.1 LoRa Network Server (see this thread)
Hidden in the same thread is the required change in /var/config/lora/local_config.json:

“gps”: true,
“gps_tty_path”:"/dev/ttyXRUSB2",

After restarting the device the log file (/var/log/lora-pkt-fwd.log) should show:

###[GPS]###
#Valid gps time reference (age: 1 sec)

Credit for this solution:
@kersing + @Osman
I have re-published their information so it is easy to find for other MultiTech owners.

Warning:
whilst this enables the GPS, the gateway will not show on ttnmapper.
I will update this post when I find a solution.

Update 1:
gateway would not show on ttnmapper, I changed the gateway to fake GPS with fixed coordinates, rebooted and it immediately appeared on TTN mapper. Then changed the gateway back to use real GPS and is stayed on TTN mapper. About 20hrs later, still running on real GPS and it’s still visible on TTN mapper.

Update 2:
commissioned a new gateway today, not showing on ttnmapper, switched GPS from off to fake to on, multiple times, but can’t make the gateway appear on the mapper. So what I’ve seen with the other gateway was a fluke.


(Heath Raftery) #2

Interesting finding. Keen to hear people’s experiences here. I suspect if it proves useful, it could be rolled in as a default in the TTN configuration. Here’s a couple of things to keep in mind:

  • Most (all?) current generation Conduit models like the 246 and the 247 have GPS built-in. Older models like the 210 don’t.
  • The Conduits however do not come with a GPS antenna - MultiTech list one (ANGPS-1MM) but none of the usual distributors have stock.
  • Naturally, to get a GPS fix you need an antenna with a clear view of the sky.

(Helioz) #3

@hraftery, the conduit 266 (IP67) version I purchased was supplied with both LoRa and GPS antennas.
Could be specific to the AU dealer where I bought it?