Electric fields are created by differences in voltage: the higher the voltage, the stronger the resultant field. Magnetic fields are created whenever an electric current flows through a conductor. Manufacturers of modern PEMF systems are using different concepts of conductive designs. The most simple and cheapest approach is the use of flexible, insulated mesh wire coils of all kinds of shapes and sizes (round, oval, square). Companies using this concept usually advertise the advantage of better transport handling since the applicators can be rolled. However, the major disadvantage of this concept is the inevitable spacing between consecutive, insulated windings which distorts the magnetic field lines leading to an impure signal, consequently diminishing the inductive force. High-end PEMF devices solely utilize pure, uninsulated and solid copper coils, assuring an uninterrupted signal structure which then creates the highest inductive force. Meaningful clinical study designs usually use prototypes which offer copper coils, known to be the most effective (Reference: NASA study for stem cell growth).
