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Where can i find the format of the UDP message that SmartSDR logger send when i log a QSO

I am trying to write a utility to receive the WSJT-X format UDP grams so that i can log the QSO in CloudLog but i can't find the format anywhere


  • KD0RC
    KD0RC Member, Super Elmer Moderator

    Hi Eric, The radio uses UDP for discovery and for audio/video (Vita-49 protocol). All else goes via the TCP/IP API.

    Take a look at the API documents to get an idea of how it works.

    There is also a C# FlexLib that you can use to access the API from a Windows DotNet environment. I recommend this if you are programming for Windows.

    FlexLib: Class List (flexradio.com)

    Node Red is also available. Dave, WO2X and Alan, WA9WUD have built some sophisticated flows for Node Red that you might be able to capitalize on. Sorry, I don't have a working link for Node Red at the moment, but someone here can point you in the right direction if you ask.

  • AA5SH
    AA5SH Member ✭✭
    edited September 2022

    They are defined here in the wsjt-x source code and there are examples also on sourceforge.

    I couldn't paste the link. But just put https at the beginning should get you there.


    Good Luck

    Michael, AA5SH

  • AA5SH
    AA5SH Member ✭✭
    edited September 2022

    Sorry wrong hpp file, I added the right one. Starts around like 117 or so.

  • Eric_M0REQ
    Eric_M0REQ Member ✭✭
    Ok thanks I found that the payload in the UDP message is ADIF format. It threw me as it looks a bit like JSON but isn’t. Fortunately CloudLog expects ADIF wrapped in a JSON envelope.