I just bought my wife a new Vizio 22 inch HD TV for her desk. She likes to watch tv while doing computer stuff. The only connection near the desk is a coax cable connector that terminates in the basement where I have a new HR20-700 that powers three tvs in the house. Given that there is ony a coax wire running to her desk, is there any kind of converter I can get that will allow her to get an HD picture?