摘要 |
<p>A power supply for high voltage, low current gas discharge tubes such as neon, argon, and mercury vapor. A free running, flyback oscillator (34), converts D.C. voltage energy into radio frequency energy by means of a compact, ferrite transformer (98) and associated circuitry. The primary winding (L5) is tuned by a resonant capacitor (C6) and driven by a power transistor (Q1). A high voltage, centertapped winding of a ferrite transformer (98) drives the gas tube load (38) directly. A feedback winding (L1) arranged across the transistor base and emitter junction sustains oscillation and controls the drive level of the transistor (Q1) by means of a regulating circuit (42) which controls the amplitude of the current. Oscillator starting is achieved by means of an on-off switch (32) which supplies a single starting pulse to the power transistor (Q1) or by means if a time delayed starting pulse.</p> |