A corona discharge beam therapy system adapted to project the beam onto the skin surface of a living body overlying a problem region, the beam serving to relieve pain and to obtain other beneficial effects. The system includes an energy-generating unit in which a radio-frequency carrier is overmodulated by a sonic signal to produce periodic bursts of radio-frequency energy whose repetition rate corresponds to the frequency of the signal. The output of the unit is fed to a tank circuit tuned to the carrier frequency and housed within the barrel of a portable applicator gun. Supported within the barrel and coupled to the tank circuit is a discharge electrode whose tip is adjacent the mouth of the barrel whereby a corona discharge beam is projected from the tip. The tank circuit which includes a tank coil and an output coil coupled to the tank coil is formed by a series of Pie sections in spaced relation mounted on an insulating tube having ventilating slots in the spaces between the sections. A motor-driven ventilator fan mounted on one end of the tube blows cooling air therein which is discharged from the slots to prevent overheating of the tank circuit and to maintain the efficiency of the unit even after prolonged operation.
