For a start, you do not have a digital ariel, they don't exist, despite what you've been told or heard. If your analoque signal was good on your ariel, your digital signal will be good. As the signal is line of sight from the transmitter to your ariel, anything that comes between the transmitter and your ariel will disrupt the signal and your picture / sound will break up, simples
Alexandre Meerkat, June 2011