Signals, systems and networks.Two-poles, Kirchhoff’s laws. Linear resistive networks. The complete and the reduced sets of network equations. Regularity of the network. Superposition principle. Series and parallel connection of resistrors, voltage splitting, current splitting. Delta-Wye transformation. Equivalent generators. Power matching. Node analysis. Loop analysis. Coupled two-poles. Ideal transformer, controlled sources, ideal amplifier, gyrator. Linear two-ports; reciprocity, symmetry passivity. Equivalents of reciprocal and non-reciprocal two-ports. Input and transfer quantities of loaded two-ports. Capacitor, inductor, coupling. Network equations. Regularity. Initial values. State variable description. Solution of the state variable description: free and excited components. First and higher order networks. Asymptotic stability. Dirac impulse. Impulse response and its application. Input-output stability (BIBO). Sinusoidal signal, phasor representation. Impedance, transfer coefficient. Calculation methods. Powers, power matching. Three-phase networks, symmetric and general systems. The transfer characteristic and its graphical representation by the Nyquist- and Bode-plot. Fourier-series form of forced response to periodic excitation. Mean values and other characteristic quantities. Spectral representation of signals, Fourier transforms. Bandwidth of the signal and of the system. Distortionless signal transfer. Band-limited signals, sampling. (6 credits)