| 摘要 |
A pulse circuit is provided for switching a grid electrode of an electron beam generator having a cathode electrode at a very high potential relative to ground. The grid electrode is to be switched between two control voltages (+V, -V) of opposite polarity by first and second switching devices (TS1, TS2) each operable to connect one of the control voltages to the grid electrode. A pair of control devices (TC1, TC2) is provided, each associated with a separate one of the switching devices (TS1, TS2) and operable to switch off the associated switching device. A first pulse transformer (TR1, TR2) is provided having a primary winding to which pulses may be applied substantially at ground potential and a secondary winding operating at the potential of the cathode. A pulse amplifier (TA1-TA2, TA3-TA4) is connected between that secondary winding and the primary winding of a second or third pulse transformer (TR2, TR3). Each of these has two secondary windings one of which is connected to one of the switching devices (TS1, TS2) whilst the other is connected to the control device (TC1, TC2) associated with the other switching device. The application of a pulse to the first pulse transformer causes the grid electrode to be disconnected from the control voltage of one polarity and connected to the control voltage of the opposite polarity. |
