I didnt even send for one when Uncle Sam handed them out for free haha... I immediatley threw out all of my old HEAVY ANALOG tv sets in the the local dump and replaced with the new HDTVs. We use the VIZIO flat screen models here.
You might take you older TV into the house and see if it works in there - You might not have a connection in the bedroom setup right. Some of those you had to add a jumper f-connector cable in the living room to get the bed room TV to work????
Someone posted a jumper cable inisde a cabinet picture similar to this a week or so ago that connected their bedroom TV to the main cable TV hookup
You need to do something there to prove your connection is getting a signal from the cable hookup before buying anything. Move a good known working TV back there and see if it works or not.