The article describes a device that converts mains voltage into the electromagnetic pulse fields of various frequencies. The device differs from the existing ones by a number of improvements, simple technical design, safety for service personnel and the environment, and low energy consumption. The methods for using the device for pre-sowing seed treatment with the aim of increasing sowing and yielding qualities, as well as suppressing pathogenic mycoflora, processing plant raw materials, in particular teas, medicinal herbs during fermentation are presented. In the fermented material, improved taste and organoleptic properties, weak aftertaste of plant raw materials and no unpleasant odor were observed.