Digital See Also: Analog, Digital-To-Analog Conversion Digital refers to data that can have a value of zero or one. Digital Signal In a digital environment, the analog Sound Wave is converted into a digital signal (zeros and ones) through two processes called Pulse Amplitude Modulation and Pulse Code Modulation. The digital representation of the voice is similar to how Morse Code used dots and dashes to transmit conversation. While all signals, whatever their type, lose strength over distance and quality due to Noise or other extraneous factors. Digital signals, however, have one distinct advantage over their analog equivalent. Analog signals must be amplified (see Amplifier), noise and all, to be transmitted over long distances. Digital signals are repeated or regenerated and new error-free signals sent. As long as the receiver recognizes digital signals as zeros or ones, regardless of the errors introduced in transmission, new zeros or ones can be sent (see the figure at the right). The Repeater recognizes the distorted signal and reconstructs the original sequence of zeros and ones. The repeater then reproduces the signal and sends it to the next destination in the network. The repeaters are placed as needed, depending on the type of communication. With digital transmission and repeaters calls traveling 10 miles share the same quality as calls traveling 1,000 miles.