No you will not be able to do it. If it is older digital box (MPEG 2) its authentication with the cable company will be based on Receiver ID. The Receiver ID must be enabled in CAS (Conditional Access System) at your local cable company, in order for that receiver to decrypt the signal (get the decryption codeword). Some newer MPEG-2 boxes, and all MPEG-4 H264 boxes (also called HDTV boxes) use smart cards, which again, must be enabled at cable company's CAS in order for the receiver/box to decrypt the signal.
So the simple answer is - NO. Digital cable in the DR is put in place to prevent people from getting free cable, not to allow it.