Introduction to signals and systems. Fundamental principles of electric circuits (current, voltage, Kirchhoff laws, introductory concepts of topology of circuits etc.). Basic circuit elements (resistor, capacitor, inductor, current and voltage sources – both independent and dependent). Theorems of electric circuits. Theorems of Thevenin, Norton, Kennely, transformation of sources – symmetric networks. Elementary transient phenomena: circuits of 1st and 2nd order – use of differential equations and Laplace transforms. Networks in the sinusoidal steady state: use of phasors, impedance, real – reactive – apparent – complex power. Three-phase networks: methods of analysis, calculation and measurement of power in three-phase networks.