摘要 |
<p>An electronic ballast for a fluorescent lamp (34) recitifies and filters the A.C. main voltage (14, 16) to produce a D.C. voltage. This D.C. voltage is applied to a class B transistor (Q1, Q2) inverter which operates in the 15-30 kHz frequency range to generate a stepped-up voltage which is A.C. coupled to the fluorescent lamp. The fluorescent lamp (34) is operated without the cathode heaters at high efficiency and longer lamp life. Fluorescent lamps considered to be burned-out when utilized with conventional ballasts, due to heater failure or loss of gas, can be illuminated.</p> |