Connecting is easy - just plug a suitable fiber optic cable at the output of the device that you want to connect the audio equipment, then from there to the digital input of the converter, and then only the usual audio cable from the converter to the stereo. (Do not forget to plug the converter also to connect).
In our case, I have connected a SmartTV of "LG" with a stereo system from 1995 ("Hanseatic") and it works absolutely perfectly.