The apparatus "Stimul-1" has been designed and recommended for batch production, its purpose being broad application in the medical practice of electrical stimulation of the muscles. For stimulation is used sinusoidal a.c. current with frequency of 2 kHz, which produces and effective contraction of the muscles without causing any sensation of pain. The unit is constructed by using up-to-date components, including microminiature logic circuits, operational amplifiers and field-effect transistors.