In order for Slingbox to work properly for you, you will need a outputting video source. A cable box with existing cable service, a satellite receiver with existing service. Your other option would be a digital tuner, this will give you a few channels , but not many. You could plug it into a DVD player, although if you are watching it away from home, you will be watching the same movie over and over. Ideally a Cable box with cable service or Satellite Receiver with service would be best. Initially most Slingbox customers are using it so they can watch their already existing television service away from home. I have put a link below to give you a bit more information. I hope this helps!!!
Sling Media Support