Abstract: The invention relates to a continuous voltage converter with soft switching, comprising a transformer (Np, Ns) whose primary is particularly of the type with a half-bridge mounting and is adapted to be connected to a source of input voltage (Ve) by means of two electronic switches (INT1, INT2) and whose secondary, of the mono-alternating type, is adapted to be connected to a load by means of an inductance in series (L2) and means (1 to 3, G1, G2) to control alternatingly the two switches, at fixed frequency, according to a regulation by modification of the pulse width as a function of the output voltage (Vo), so as to provide to said primary a switching at zero voltage, said converter being characterized in that said secondary comprises moreover a resonant circuit (L1, C1) so as to provide for said secondary a quasi-resonant switching at zero current.

Abstract: The disclosure relates to cathode-ray tubes that have to be used at a low level of luminance. A zone of the screen of the tube is covered with a luminophore of high sensitivity and is associated with a luminance sensor by an optic fiber that measures the luminance of the tube at chosen instants corresponding to an excitation of said luminophore by an electron beam deflected towards the part of the zone facing the fiber. The luminance signal is compared with a desired value and the result of the comparison is used to modify the cut-off voltage of the tube through action on the voltage of the cathode or of the Wehnelt gate of the tube. This device can be applied to cathode-ray tubes used in aircraft.

Abstract: Disclosed is a supply of the AC-DC converter type where the regulation is achieved by successive operations for charging and discharging a capacitor. The supply includes an input oscillator circuit, the period of which is very small as compared with that of the input AC voltage. A first switch is closed during the time necessary for the charging of the capacitor of the oscillator circuit. When it opens, a second switch gets closed to enable the transfer of energy towards the load. The regulation is done by an oscillator circuit which is controlled by an error voltage on the load and which triggers a monostable trigger circuit to close the first switch and open the second one during the period when this monostable trigger circuit is in its quasi-stable state.