Method and apparatus for testing a communications wire

摘要

The status of communications by a specific metallic cable set among a number of metallic cables and that are arranged close to each other in a transmission line(1) is inspected. An inspection signal is supplied to flow in one metallic cable(2), an interference signal flowing in other metallic cable(3) is measured in response to the flow of this inspection signal, and based on the relationship between the inspection signal and the interference signal, it is judged whether or not the status of communications by the specific metallic cable set is fine. A measuring device(21) measures components other than a descending carrier to be received by a transmitter-receiver(22) from a repeater(10), and includes information on the components in an ascending carrier. The repeater(10) extracts the information on the components from the ascending carrier received from the one transmitter-receiver(22), and based on the extracted information, makes the frequency characteristics of the one metallic cable(22) different from that of other metallic cable(23) so that the components are reduced.