A data transmission system for interfacing with a telephone communication line includes a bar code reader and a hand-held bar code scanning device for reading bar coded information, such as a lottery ticket number, and generating electrical signals representative thereof. The system also includes a program-storing memory and a processor for converting the electrical signals to a format recognizable by a telephone system, i.e. dial pulses or dual tone signals. A display is provided for displaying the electrical signals. A telephone network interface is employed to transmit the telephone system recognizable signals to the telephone line.