Power sources, chemical current sources, transformers, rectifiers, voltage multipliers, voltage rectifiers, impulse sources, over-voltage and over-current power sources. High-frequency amplifiers, parasitic impedance compensation, h-f amplifiers construction fundamentals. Amplitude modulation, modulators and demodulators, DSB and SSB modulation. Frequency and phase modulation, modulators and demodulators. Impulse modulation. Convertor, additive a multiplicative. Frequency multiplication and division. Phase hangings and its applications.