Abstract: The invention concerns a process and a device ensuring the fixation on the neck of a cathode tube of the deflection yoke of the tube. According to the invention, the deflection yoke 3 is fixed after its positioning has been determined between a fixed abutment 9 which may be adjustable in position and an elastic abutment 6 which presses the yoke 3 against the abutment 9. The invention applies especially to tubes adapted to be fitted to color television receiver appliances.

Abstract: At least one elastic collar is mounted in extension around the neck of a color television tube and behind the deflection yoke. A static convergence correction unit in the form of a cylindrical ring is placed around the neck with a predetermined clearance. The ring is slidably fitted over the elastic collar or collars which are thus compressed when the ring has been placed in the desired position. This permits suppression of an air-gap and accurate positioning of the ring on the neck of the tube.

Abstract: The invention refers to a process and a machine making it possible to achieve improved winding of turns of electrical wire on a cathode ray tube deflection ring. According to the invention, the machine includes three axes X, Y, Z with motor means. The winders 12 rotate around axis Z to achieve turns of winding. They are supported by a rotatable column 11 around axis X to the winding plane. The deflecting ring 15 is mounted pivotally around axis X on a fixed support 4. The machine also includes pairing means for controlling electric motor means 5, 14. It is able to perform windings of desired incline without reducing the work speed of the winders 12.

Abstract: A process of analysis of convergence along two orthogonal components of the three guns in a color television tube with ganged guns involves, for example, placing an analysis slit 20 in front of the screen of the cathode-ray tube in order to observe at least three luminophore columns 15 of different colors in full width, of causing a luminous line of a single color to pass by, turning on only the corresponding gun in front of said slit, and of measuring the current in the deviator of the cathode-ray tube for which the maximum light intensity is observed through the slit, and of beginning these operations again for each of the three colors, the measured values making it possible to deduce the convergence gaps of the beams at the placement of the slit. The invention allows automatic convergence correction of the cathode-ray tube.

Abstract: The blocking voltage of an electron gun is corrected by periodically removing an input video signal and driving a cathode with a DC stabilizing voltage. A pulse perturbation is impressed upon a control grid and the cathode momentarily conducts more heavily to exceed a predetermined threshold corresponding to the limit of a black CRT picture. A feedback loop detects a response signal from the perturbation of cathode current and stores the response signal in a memory, the latter determining the corrected blocking voltage during normal operation of the gun.

Abstract: Improvements to combined power supply and horizontal deflection devices in a television receiver.According to the invention, the line transformer includes a winding W.sub.1 for maintaining an oscillation circuit including the deflector Ly of the cathode-ray tube and a winding W.sub.2 which may be connected to a power supply source E through a controlled switch I.sub.2 ; the winding W.sub.1 is not effectively put into service for the sweep until a switch I.sub.3 or I'.sub.3 using a diode D'.sub.3 with a relatively long recovery time and operating in phase opposition with respect to I.sub.2 is closed, so that the temporary short-circuit of winding W.sub.1 during a sweep trace is not felt by the power supply source E.The invention mainly permits powering all the circuits of a television set from a single transformer, the line transformer.

Abstract: A shadow-mask cathode ray tube for the visualization of colors, such as in television, where the peripheral edge of the mask is rigid with the frame fixed on the tube plate and is in contact with said frame only in areas spaced from each other. The frame is formed with bosses providing its contact in reduced cross-section areas spaced from each other with the edge of the mask.

Abstract: Apparatus is disclosed for generating a blanking voltage for electron guns in cathode ray tubes, as used, for example, in color television displays. Apparatus utilizes circuitry including a video voltage amplifier having a control input. A feedback loop, connected between the junction of the cathode and video voltage amplifier output at one terminal, and the control input at the other, modifies the blanking voltage in response to samples of the cathode current taken when the video signal is zero.

Abstract: An exposure lighthouse for use in printing screen structures for cathode-ray tubes comprising a lens assembly including a diffracting optical element, a main intensity-correction filter and a supplemental intensity-correction filter in series with the main filter. Both of the filters comprise preformed carbon particles in a light - transmitting binder.