TVtechmaniac is spot on. I own this unit and it has one DTV input which is 480p/1080i. Plug your component apple tv into this and you should be good to go. Im assuming the atv auto configs? If not, set to 1080i and you should be good to go.
The component 1 and component 2 inputs only go to 480i and 480p. The Apple TV must be plugged into the DTV input which will accept a 1080i signal.
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