If I understand you question, I believe the answer is No. This HD tuner does not take SD signals and "make" them HD, but what it does do is allow you to receive HD broadcast signals and route them to your HD-ready TV. I have an HD-ready TV, but to view HD broadcasts I need an HD tuner, so this would solve this for me. On this tuner, it also allows SD (Standard Def) broadcast signals to reach your TV too. My HDTV comes with a built-in SD tuner (most do) but to watch HD channels, I need an HD tuner. Now, the big question is: If I (or you) bought this HD tuner, would you still need to upgrade your cable service to "digital" so you could receive the HD signals they broadcast? I believe so. Or, get Dish and pay for their HD signals. For both cable and satellite services, they would be "selling" or "renting" your their HD receiver at add'l cost, so in theory, the tuner you are considering would eliminate the need to buy their tuner.
I am looking for a reciever that will be able to take My already existing Cable Channels and turn them into HD without having to pay for the Monthly charge of the Direct TV....
http://www.refurbdepot.com/productdetails2.cfm?Product_ID=3719
Will this reciever do what i am looking for???

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