| 摘要 |
949,829. Supply systems for discharge lamps. PHILIPS ELECTRICAL INDUSTRIES Ltd. April 27, 1960 [April 30, 1959], No. 14778/60. Heading H2H. [Also in Division H3] A transistor oscillator supplying a gas discharge tube 8, e.g. a fluorescent lamp, and fed from a battery 3, has positive feedback provided through an LC series circuit 6, 7 across a part of which the tube is connected. As shown, the oscillator supplies a square wave voltage from a transformer 4 to the LC circuit which, due to resonance, provided a higher voltage to the lamp 8. Feedback is via a second transformer 5, and an RC circuit 9, 10, 11 ensures a starting pulse for the oscillator; the lamp ignites immediately. The lamp may alternatively be connected across part or all of the choke and in an alternative oscillator the transistors are in series across the supply 3 and are controlled in phase opposition by separate windings on transformer 5; transformer 4 is dispensed with. The output is then derived via a capacitor, between the common point of the transistors and a battery terminal. A further alternative, comprising one transistor, a transformer and a limiter diode, is mentioned.
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