Surgical diathermy apparatus.
A surgical diathermy apparatus which virtually eliminates the possibility of burns to the patient from faulty return current electrodes applied to the skin, and other causes. A capacitive neutral plate system is employed as return electrodes, along with injection of a compensating potential in series opposition to the potential drop across the capacitive neutral plate system. The apparatus can also incorporate testing, measuring, alarm, and safety cut-off systems. The invention can be applied to completely new diathermy apparatus, or as a retrofit improvement to existing equipment.