Electrotherapy equipment for treatment by stimulation - uses two or more modulated frequency currents, modulated by sync. and asynchronous voltages with respect to interference frequency

摘要

Electro-therapy equipment is for application of a stimulating current. Two or more m.f. currents are modulated. Their frequencies differ by a small amount of their phases rhymically shifted w.r.t. each other. They cause stimulation in a selectable region through interference phenomena. The current sources are independent. At least one of the current sources has an amplitude modulating circuit. A synchronous and an asynchronous modulating voltage w.r.t. the interference frequency are delivered to the circuit for amplitude modulation.