We have a big screen TV one night we were watching it an it just went out no sound no picture some one said it might be the power moudular any sujustions and how do we repair it thankyou

Hi folks! Just found this wonderful site and I'm hoping someone can help. We live in a rural area and put in a DSS system 6 months ago. We were able to receive our local network stations (NBC, CBS, ABC and FOX) just fine with an amplified RCA tabletop antenna. Two months ago we bought a 50" big screen, and while we are able to receive adequate reception from CBS and ABC with the tabletop antenna, NBC and FOX don't come in at all. Up to this point, it wasn't a big deal, but it's almost football season and the Olympics are on NBC! The local affiliates have refused to grant a waiver for us to receive those two network feeds through our satellite. The local cable company does not provide a local only tier. I would have to pay $29 a month for their "basic" service, which of course would duplicate a lot of the channels I get with the satellite. Radio Shack tells me the big screen TV requires a stronger signal to pick up the local networks and that I need a $150 roof top antenna, which is basically the top of the line they carry. 1) Is the information Radio Shack have given corrent? Do I really need a $150 antenna or will a less expensive one work as well? None of the local stations are more than 30 miles away. 2) Is there any other viable alternative to a rooftop antenna? Thanks in advance for the info!