Is it possible to receive HD over the air channels thourh Direct TV or Dish Network HD receivers without subscribing to their programming? I have a HD ready TV but not the tuner so I am trying to find out if I can use the Tuner from the DTV or DN tuner. Thanks in advance.

sorry, but no. the receiver has to be activated.
you can get an off air HD tuner. Get ready to spend some Bucks.