Diagnostics of technical state of stretched engineering underground communications by electromagnetic methods

In this paper electromagnetic methods of diagnostics of technical state of stretched engineering underground communications (such as cables or pipelines) are considered. Formulae for calculating the components of underground communication electromagnetic field are presented. Technical characteristics of one of the devices for searching underground objects, determination of their coordinates and insulation damages which was designed in the Physico-mechanical Institute of the National Academy of Sciences of Ukraine are described.