We posted this Tweet about HDSDR a month or so ago:
Well, we just delivered, and we are now providing the necessary files for interfacing the popular and free SDR software—HDSDR—for all of our receivers. This includes all SA and BB series analyzers.
Combining the HDSDR software with your Signal Hound spectrum analyzer turns the system into a flexible software radio.
You can download the files and setup guide on our White Papers and App Notes page.