Abstract: A tuned switched-mode power supply for producing a stabilized d.c. output voltage by controlling the duration of the conducting period of a bidirectional switch as a function of the output voltage. The drive switching pulses for the switch are subjected to a pulse duration modulation control followed by a frequency control in such a way that the switch-off pulses have a substantially pre-determined time duration which is longer than half a cycle of the tuning frequency of the power supply.

Abstract: A color picture display device having a circuit for generating a screen grid voltage derived from the line deflection generator, while the high tension generator is separated. Via a resistance element, the screen grid is coupled to a source which generates a parabolic voltage of the field frequency with a curvature opposite to that obtained by rectifying the line flyback pulses owing to the east-west modulation, the resistance element, for example a voltage-dependent resistor, having in operation, a dynamic resistance which is many times lower than the static resistance thereof.

Abstract: A line deflection current generator and a diode modulator for influencing the amplitude of the generated deflection current but without influencing the d.c. voltages which are also generated by the generator, a controllable switching device, for example, the series arrangement of a coil and a thyristor being included in parallel with one of the diodes of the diode modulator and with the opposite direction of conduction. This controllable switching device can also serve as control element for the amplitude modulation.

Abstract: Line deflection circuit in which the deflection coil is east-west modulated. In order to cancel an east-west dependent horizontal linearity defect the inductance value of the linearity correction coil is made independent of the field frequency, for example by means of a compensating current. In an embodiment this current is supplied by the shunt coil of the east-west modulator.

Abstract: A circuit arrangement for generating in a color picture display device a sawtooth correction current of line frequency flowing through the line deflection coils and having an amplitude varying at field frequency for the purpose of obtaining a better color superposition in the corners of the screen of the display tube. The circuit arrangement is provided with a modulator which includes an electronic switch switching at the line frequency, which connects a field generator to a resonant circuit during the line scan period, which resonant circuit includes in a parallel arrangement a capacitor and an inductance including the line deflection coil, the period of the resonant frequency of the resonant circuit being substantially twice the line flyback period.