The book provides the most complete description of devices on field transistors. Particular attention is paid to new classes of these devices - powerful field transistors of various types, IGBT and integrated circuits based on them. The basics of the theory, calculation and description of the operation of a variety of schemes on field transistors are given: keys, electronic regulators, pulse and resonant power sources, high-speed pulse devices, high-power pulse generators, amplifiers and generators of various frequencies. Reference data for all domestic powerful field transistors and the most common foreign-made devices. The presentation of this class of devices and devices based on them on the Internet is described, the method of their mathematical modeling and debugging is given. Designed for specialists in radio engineering and electronics, students of technical universities and trained radio amateurs.