Remote monitoring and fault locating system - has characteristic-frequency oscillators at nodes of transmission network

摘要

The monitoring and fault-locating system, esp. for cable t.v. networks, has the oscillators of given frequency located at or in the branching points of the associated branches of the monitored transmission plane associated with the next higher transmission plane. The characteristic frequencies of these oscillators are supplied to the branching points in a branch in the next higher transmission plane. All message switches in a monitored branch are interrelated electrically such that one or more modulating signals can be generated-from the signals resulting from these switches-with which the oscillator associated with that branch is modulated. Faults are located by analysing oscillator frequencies and their modulation.