You can now output to SDI using OBS. Follow the instructions below to connect OBS to your SDI output.
Within OBS, open the Tools dropdown menu, then select Decklink Output.
Choose the Device you wish to use. In this example it is the Decklink Quad (1).
Choose which Mode to use (1080p50 etc).
Select a Keyer, it needs to be External.
Click the Start button and you will see your output.