a tv with a built-in tuner will be able to receive all unscrabled channels, which is usually the local HD channels (ABC, CBS, etc.) some may even be able to receive encrypted channels for awhile such as TNT-HD and ESPN-HD. These instances are very very rare. But once again, if your tv has a built-in tuner, connecting your comcast coax directly to tv should get you at the very least local HD
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Sony WEGA KDL-52XBR4 Daddy's Room
Onkyo TX-SR705
Klipsch Synergy Series Quintet 100-Watt 5-Piece Home Theater Speaker System
Klipsch 12" 650W Powered Subwoofer
Logitech Harmony 880
HR 20-600& HR 21-200, Direct TV
PS3 60GB  ,
PS3 80GB
HD-A30
HD-A2 
Nintiendo Wii
Sony WEGA KDF-55WF655 retired to family living room
Ready Nas Pro Duo 1.5 TB Media Server
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