A:Answer Is it possible that you are scanning for cable and not over the air channels ? The scan gives you a choice, when in doubt, scan for both, it will not hurt (or help) but it will take longer. If you are sure you are scanning correctly, is it possible that your antenna is not pulling in a usable signal ? Unless you live within 25 miles of a TV tower, you probably need a signal amplifier or a roof antenna or both.