A tunable and aimable artificial lightning producing device for tetanizing human voluntary muscle, disabling vehicular electronic ignition systems, and for pre-detonating wired explosives. A spark gap shaping apparatus controls a spark generated by a Tesla coil. A first stage directionalizer warps a normally spherical plasma field from the Tesla coil into an oval plasma field for confining the spark to within that shape. A second stage directionalizer converges multiple beams to successive points just ahead of a plasma field created by the first stage directionalizer without ionizing the beams, thereby maintaining ionization of a path of the spark. The spark is progressively arced to these points, thereby maintaining the path of the spark.

Invasive hyperthermia apparatus includes an electromagnetic energy radiation source, and a plurality of applicators. Each applicator is adapted for insertion into body tissue and radiating electromagnetic energy therein. Interconnected between the applicators and the radiation source are a power splitter and a plurality of line stretchers for providing the applicator with electromagnetic energy in a preselected frequency - phase power relationship. The applicators, power splitter and line stretchers are operative for causing constructive interference between emitted electromagnetic radiation when the applicators are inserted into body tissue in a preselected spaced apart relationship.

A hyperthermia apparatus primarily applicable to the treatment of tumors comprises at least three high-frequency generators connected to three electrodes. The electrodes are intended to be coupled to a patient's body which constitutes the load, thus producing a higher temperature rise in the vicinity of a fictitious electrode in the body. The generators have adjustable phases and amplitudes, the output of each generator being connected to each of the three electrodes.

A cardiac pacing apparatus and method. A cardiac pacing apparatus (24) provides a cardiac pacing signal to a plurality of electrode pairs (20, 22), each comprising a positive electrode (20a, 22a) and a negative electrode (20b, 22b). A plurality of isolated current sources (30, 32) supply the electrode pairs with separate electric pacing currents, each small enough in magnitude so as to avoid patient discomfort or burning. The plurality of pacing currents delivered to the electrode pairs add to produce a total cardiac pacing current of sufficient magnitude to cause contraction of a heart muscle through which the pacing currents flow.

A system and corresponding method for creating hyperthermia in target tissue has a computer control for applied electromagnetic radiation (EMR) in the HF, VHF and UHF microwave region. A real time thermal profile of the target and electric field readings provide feedback to the control. The frequency, amplitude, and relative phase of the EMR can be varied as necessary to create desired hyperthermia heating patterns in the target. The system utilizes controlled constructive interference between EMR emitted by several applicators in order to provide improved heating in the central regions of the target. Several different applicator arrays are suitable for use with the system, and comprise generally cylindrical annuli which emit radiation toward a central axis.