| 摘要 |
<p>A capacitive load, such as an accelerating electrode of a polychromatic cathode-ray tube, is energized with a recurrent stepped voltage in the VHT (very high tension) range via at least two sources of direct current. The first source is directly connected across the load capacitance through a first charging circuit including a first winding which is inductively coupled with a second winding in a discharge circuit of a second capacitance connected across the second source by way of a second charging circuit. A control circuit so times the charging and discharging of the two capacitances that the voltage of the load capacitance is held at a basic level, corresponding to that of the first source, during an initial phase of the period T of the stepped output voltage and is thereafter progressively increased to several elevated levels by the transfer of charge increments from the second capacitance, the latter being repeatedly charged within each period T during consecutive intervals followed by a final interval after the last transfer. To help stabilize the output voltage at its elevated levels, a third capacitance may be charged for brief instants from a third source and thereafter discharged, a multiplicity of times within each interval except the first, through a third winding inductively coupled with the first and second windings, thereby generating a sawtooth pattern with a constant mean voltage.</p> |
