A pulse generator including a control logic operating, by control pulses, a switch connected on the input side with a voltage supply unit and delivering a pulse voltage on the output side, there is connected, between control logic and the switch, a capacitor, which decreases the pulse voltage when the pulse frequencies are too low, and, additionally, arranged between voltage supply unit and switch, an RC-member, which decreases the pulse voltages when the repetition rates of the control pulses a...