The main information about the theory and practice of electrical measurements of the parameters of modern wired communication devices, the parameters of transmitted signals, the parameters of interference and the results of their impact on transmission, passage through the tract and reception of signals is presented .. In each chapter there are practical and theoretical tasks that contribute to a deeper assimilation of the material. The textbook is intended for students of technical schools of communication . Preface 3. Introduction 61. Tasks and types of measurement in wired communication 62. Stages of measuring experiment 73. Features of methods and equipment for measurements in wired communication 104. Trends in the development of measuring communication technology in the USSR 10. Chapter 1. Special units of measurement used in wired communication technology 12. Chapter 2. Exemplary devices used in communication technique 22. Chapter 3. Direct current line measurements 38. Chapter 4. Determination of the distance to the places of damage on air and cable communication lines with direct current 57. Chapter 5. Determination of the distance to the place of damage of air and cable communication lines with alternating current 76. Chapter 6. Pulsed measurement method on communication lines 91. Chapter 7. Measurement of attenuation and amplification of quadripoles 107. Chapter 8. Current sources in measuring circuits 148. Chapter 9. Electronic oscilloscope 169. Chapter 10. Voltage and current meters and indicators, measuring panels 191. Chapter 11. Frequency Measurement 228. Chapter 12. AC resistance measurement 239. Chapter 13. Measurement of Nonlinear Distortions 255. Chapter 14. Measuring circuits and communication channels with alternating current 272. Application. Solutions to problems 304. References 339