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

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.