Abstract: An electronic transformer system for illuminating neon lamps includes a counterphase oscillator coupled to a leakage reactance power transference transformer. The power transference transformer has a secondary wound on a multiple section bobbin in which adjacent sections are separated from each other by a dielectric material. The leakage reactance power transference transformer has a feedback winding which is coupled in series to the primary winding of a pulse generator base driving transformer. The pulse generator base driving transformer in turn provides periodic pulses to the counterphase oscillator to reverse current flow in the primary of the leakage reactance power transference transformer. The electronic transformer system may be powered by commercial alternating current through a full wave rectifier, or by a direct current power supply.

Abstract: An electronic ballast employs an electronic inverter which drives a main power transformer across the output of which terminations are connected for a plurality of fluorescent lamps. A high impedance capacitor is connected in parallel across at least one and less than all of the fluorescent lamps. An auxiliary transformer is interposed between the output of the main power transformer and the cathode elements of the fluorescent lamps. Upon start-up, the high impedance capacitor initially creates a bypass around lamps with which it is connected in parallel to thereby apply the entire high voltage output of the power transformer to start the remaining lamps. Once these lamps are started the voltage drop thereacross is reduced to allow the high voltage output to bypass the high impedance capacitor and start the lamps connected in parallel therewith. The auxiliary transformer provides good magnetic coupling and low voltage to the cathode elements of the fluorescent lamps.