The textbook gives students an opportunity to go into the fundamentals of radio electronics and radio engineering: signals, spectrums, linear and non-linear devices, etc. The first part of the book is devoted to fundamentals of electrical engineering; it explains how to make design of networks with direct and alternating voltage sources. The second part is said about the simplest resonant circuits; spectrum of signals; transient processes in circuits; diodes, transistors and devices, based on these elements. The third part contains tasks and exercises for class- and homework, tests for control and self-control of the knowledge. The book will be useful for foreign students participating in academic mobility and studying specified specialties in European universities, for whom English is not native. This textbook introduces students to the English terminology in the field of radio electronics, radio engineering and communication technique. The book will be also interesting to Russian students from more than a hundred Russian universities focused on integration with European universities, where radio electronics, radio engineering and communication technique are studied.