The book is compiled according to the program of the eponymous course of electrical and radio engineering universities and is devoted to the theory and calculation of electrical power sources of radio engineering devices. The book contains basic information about valves, rectifiers, smoothing filters, primary sources of electric current, devices for regulating and stabilizing current and voltage. The book is intended for students of electrical and radio engineering universities as a course textbook, as well as for engineers and technicians involved in the research, design and operation of electrical power sources for radio engineering devices.