| 摘要 |
The invention concerns a ballast system for vapour discharge tubes. The tube 12 is provided with power by a ballast system comprising a transformer T which is connected to an AC power source 14 via a rectifier diode D1. The primary winding 22 of the transformer T is connected in series with the power source 14 and the incandescent electrode 30 of the tube 12 via a capacitor C2. The secondary winding 24 of the transformer T is connected in positive feedback relation to the base 44 and the emitter 42 of a transistor Tr. The collector 38 of the transistor Tr is connected to the capacitor C2. A second capacitor C3 is connected in series with the secondary winding 24 of the transformer in order to apply a voltage pulse to the second incandescent electrode 32 of the tube 12. <IMAGE> |
