Postcard (base, rover) with LoRa Serial kit setup help

GPS/GNSS
1

Hi,

Looking for some help on my setup as I am struggling. I have two Postcards with LoRa radios attached to each of them thru the UART3 radio port. The radios seem to be linking right away and always have 3 leds (they are 5’ apart for testing). I am using a L1/2/5 antenna on the base and a L1/2 antenna on the rover (ublox ann-mb).

I am running v2.3 in each postcard as well as V6 in the LG290P. Each postcard has been reset after upgrading the firmware.

I have set everything up as per the attached file.

The survey in occurs rapidly and I get an accuracy of around 17cm.

I then monitor my rover and the best I get is 1.018m accuracy (its stuck there) with a DGPS Fix state. When I check my corrections priority, I am seeing corrections over the External radio but they are somewhat old - never newer than 20sec.

Do I have something wrong with my config? I only recently toggled the low bandwidth base option but that doesn’t seem to have changed anything. With toggling the low bandwidth option for base messages, I assume the 4800 bps on the LoRa is sufficient (I can’t figure out how to get it to permanently stay at 19200.

Any help is appreciated. I’m relatively new at this - these forums are such a great resource!

Postcards (Rover, Base) and LoRa configs.pdf (267.7 KB)

2

Are your antennas outside? RTK does not work indoors.

Make sure the serial interface speeds are correct. The Postcard needs to output serial at X rate, the LoRaSerial needs to be setup to receive at X rate.

You might try connecting the TX pin on your base to the RX pin on your Rover and eliminate the radio connection for now.

Also, consider ESP-NOW. It’s a free radio for base/rover that will eliminate the LoRaSerial as a variable.

3

@sparky thanks for the reply. To answer your questions:

  • yes, both rover and base antennas are outside
  • yes, both Postcard & LoRa Serial Speeds are set the same - 115200

Thanks for the suggestion on eliminating the LoRa for now - I’ll one or both of those solutions.

Paul