I've got a 722. I am trying to hook up my antenna to the OTA jack on the box, but when I scan for channels, the box doesn't see anything. I know that the channels exist because I can hook the antenna directly into the TV and receive all the OTA channels broadcast in my area. I've called Dish tech support, but they are not helpful at all. They just tell me to get a better antenna, but I know that the antenna is sufficient to pick up the channels. Please help.