I bought a Motorola DCH6416 dual-tuner DVR from an estate sale. Is it possible to use this with a satellite provider like DirecTV? I currently use a ReplayTV 55xx but I've already replaced it once and availability is getting scarce. I was hoping to upgrade to something more 21st century. Has anyone used this configuration or know if it's possible? If not and I give it to my mother-in-law, who has Cox cable, would she be able to use it?