I am adding on and will have to get another two tuner DVR. I have a 522 which I will use in the new room and a 622 on the main tv. To replace the 522 in the old bedroom I want to go ahead and get a 622 or 722 whichever I can get the execs to allow me to have. My question is if it is being hooked up to an SD tv on tv1 can it be hooked to an old tv which just has one cable like hookup. I can get an adapter for the cable hook up but will it work? By the way I will get an HD tv in that room later, I just can't do it right now. I don't want to go to the execs and get another lease on a 522 or 625 and then have to do it later for a 622 or 722.