Abstract: A digital data transmission system eliminates the need for coaxial cable or twisted pairs as a means to eliminate noise, interference or cross talk problems. The system utilizes a multi-conductor cable having a plurality of lays of insulated conductors surrounded by an electrically conductive shield. The shield serves as a common ground and one conductor in each lay provides a reference line for that lay. Data is transmitted over lines in at least one lay, the lines for transmitting data being terminated at each cable end by their characteristic impedances with respect to the shield.