Additionally, cable-ready TV sets can display HD content without using an external box. They have a QAM tuner built-in and/or a card slot for inserting a CableCARD.
Additionally , cable - ready TV sets can display HD content without using an external box . They have a QAM tuner built - in and/or a card slot for inserting a CableCARD .
HD content can be displayed by cable-ready TVs without using what?
HD content can be displayed by cable - ready TVs without using what ?
an external box
an external box