Abstract: A passive impedance matching device incorporates a pair of power splitters, each having a transformer core with a center tapped winding shunted by a resistance having a predetermined value. The power splitter windings have their center taps connected to the input terminals. The arrangement creates a virtual ground and thus avoids the need to create an unbalanced signal. By cascading stages the input signal can be split any number of times. Unused outputs are terminated with their characteristic impedance.

Abstract: According to the present invention, a portion of an applied commercial AC supply (60 Hz) is rectified, filtered and a controllable oscillator in a pulse width modulator chip serves as a signal generator which has both duty cycle and frequency control adjustments. An output signal is coupled via an impedance matching circuit to the input primary winding of a signal transformer having a pair of secondary windings which drive a pair of tandem connected electronic switches which, in turn, are connected across a second DC supply which has a high direct current voltage derived from the input AC line voltage (110-120 V AC 60 Hz).