Subscriber terminal for monitoring radio-frequency signal ingress into cable television systems

摘要

A cable television subscriber home terminal capable of transmitting information along a cable to a central station at one of a series of predetermined return frequencies includes a receiver tuned to monitor possible ingress into the system at selected frequencies within the range of the return system frequency. A signal representing the magnitude and frequency of the detected ingress signal modulates a return signal, which is transmitted along the cable system to the headend to provide information concerning the detected ingress signal.