Abstract: A system for locating an impairment in a coaxial cable network comprises an encoder, an impairment detector, and a decoder. The encoder couples to the network at a predetermined encoding point, upstream of the impairment. The encoder automatically encodes an identification code on a signal originating downstream of the encoding point and associated with the impairment. The impairment detector couples to the network at an access point, upstream from the encoding point, and receives signals from the network. The detector is adapted to detect from the received signals the signal associated with the impairment and generate a detected version of the signal. The decoder is adapted to decode the identification code from the detected version of the impairment signal. Once the identification code is determined, the encoder and encoding point are identified, and the location of the impairment is determine to be downstream of the encoding point.