“Good luck” shouts the instructions that came with Marc’s aunt’s Sansonic DTV converter box. No, really, it says right there in all caps, “GOOD LUCK,” as in, “you have 50/50 chance your old antenna will not work well.” Yes, that’s another quote from the manual. “In her case, her luck was limited,” writes Marc, “Great reception for everything except the local PBS station, which is about the only thing she watches.” Full “Easy Install Instructions” inside…