Currently my scaler has only 1 SDI input, which has me worried. Some of the other scalers on the market have multiple SDI inputs, I don't want to be left out in the cold if and when SDI takes off. So I did some research. At this point, if you don't know, you can buy an external switch box that can allow you the ability to add as many SDI devices as you like, 5 or more from the ones I have seen. But, an external switch box is a pain in the ass, an option but, I want something easier. Called up a company called KING, they make all of these fancy adapters and custom jobbies. They make a 75ohm, BNC male to 2 BNC female adapter that converts a single SDI input into 2 SDI inputs, no switch box no problems. Your scaler SHOULD have no problem accepting SDI from either end of the splitter adapter provided only one SDI signal is being sent at a time. What I mean is that if you have an SDI equipped DVD player and an SDI equipped DTV box, only turn on ONE of the two components at a time, the one you want to watch. Turn off the one not in use and now we have 2 SDI inputs. Sounds like a good solution, you can only watch on source at a time anyway, so who cares if one component has to be turned off? My DVD player is off as I write this. Anyway, that's my finding. For now I know of no one with 2 SDI sources but, in the future, it is something to consider.