Digi SX (PRO) / Ardusimple LR (XLR) Radio compatiblity

RTK Base Setup
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I have not had a bare Digi SX rover module perform as well as my arduSimple LR with the SMA connector.

The LR without an antenna still receives more of the RTCM data then the SX with antenna while testing in my basement (tower is outside right beside me)

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Even a bare SX in Digi’s dev board misses some data. :person_shrugging:

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So after consulting with Digi support, reading docs and forum posts I think I have improved my radio config settings, in so much that my bare SX modules are performing much better if not as good as my arduSimple LR radios. Here are my config files, the base & repeaters (SX Pro or XLR) use the same config and the rovers (SX & LR) use the other one as marked.

(rename them to “.xpro” for opening with XCTU’s profile editor)
2025 New PtMP config profile - Rover - 1985 network ID - 115200.zip (97.9 KB)
2025 New PtMP config profile - Base-repeater - 1985 network ID - 115200.zip (97.9 KB)

You can open the .xpro file just like a zip file and inside the profile.xml has all the settings listed that are different then Digi’s default.

Base/Repeater

      <setting command="CM">5555555555555555555555555</setting>
      <setting command="ID">1985</setting>
      <setting command="MT">0</setting>
      <setting command="BR">1</setting>
      <setting command="PL">2</setting>
      <setting command="TO">80</setting>
      <setting command="NI">Repeater-Base</setting>
      <setting command="BD">7</setting>

Rover

      <setting command="CM">5555555555555555555555555</setting>
      <setting command="ID">1985</setting>
      <setting command="MT">0</setting>
      <setting command="BR">1</setting>
      <setting command="PL">2</setting>
      <setting command="CE">2</setting>
      <setting command="DL">0</setting>
      <setting command="TO">40</setting>
      <setting command="NI">Rover</setting>
      <setting command="BD">7</setting>
  • CM - this is how arduSimple has theirs set, I’m not sure how it should be, all radios set the same
  • ID - unique network id number should be the same on all radios
  • MT - how many times to retransmit each packet, I set mine to 0 because in 1s there will be new RTCM data again, only applies to the base/repeater radios
  • BR - RF Data rate, 1 = 110kbps, set the same on all radios
  • PL - TX Power level, 2 = max TX power, applies to base/repeaters only, rovers listen only
  • CE - Routing Mode, 0 = Standard Router (default), 2 = Non-Routing Module. It was recommended to set the rovers as CE =2 and leave the base/repeaters as default CE = 0.
  • DL - Dest addr low byte, when set to 0xFFFF all other radios will receive the data, when set to 0 no radio will listen to the data. So I set it to 0 on the rovers so that if they transmit any data, no other radio will hear it
  • TO - Transmit Options - Base/repeater set to 0x80, Rovers set to 0x40
  • NI - just a human readable name
  • BD - baud rate for the uart (serial port), 7 = 115200, this should be set to match whatever is connecting to the radio’s uart

With this config, I tested the repeater functionality by removing the rover’s antenna, moving away from the base and shielding it until it stopped receiving data, then I plugged in a 2nd base/repeater radio w/ antenna close by and the rover started receiving data again.

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