SU849543A1 - Device for horizonatal-wise centering of raster of camera tube - Google Patents

Description

(54) DEVICE FOR CENTERING THE RASTER ON THE HORIZONTAL OF THE TRANSMITTING TELEVISION TUBE

The invention relates to radio engineering and can be used in color television cameras on tubes with charge accumulation, in multi-raster systems and in black-and-white television cameras.

A device for centering a raster of a transmission television tube horizontally is known, comprising a series-connected video amplifier and an element, to the second input of which is connected the output of the first multivibrator, whose input is connected to the input of the generator of tracking pulses, to the output of which are connected in series the time discriminator, power amplifier and an actuator, a current regulator and a serially connected second multivibrator, whose input is a sync pulse input, and di frentsiruyuschy unit 1.

However, the known device does not allow precise alignment of the rasters in the camera while continuously transmitting the television image.

The purpose of the invention is to improve the accuracy of alignment.

To do this, a pulse generator, a switch, a second And element and a control unit are inputted into the known device, the output of which is connected to the first input of the second And element, the second input of which is connected to the output of the first And element, and the output of the second And element is connected to the second input of a temporary discriminator, the switch input is connected to the output of the execution unit, and the switch output is connected to the input of the current controller, and the input of the pulse generator is connected to the output of the differentiating unit, and the output is connected to the inputs of the first of the following pulses with a multivibrator.

The drawing shows a structural electrical circuit of the proposed device.

15 A device for centering a raster horizontally on a transmitting television tube comprises a video amplifier 1, the first and second elements I 2 and 3, the time discriminator 4, the power amplifier 5, the executive unit 6, the switch 7, the current regulator 8,

Claims (1)

 the first and second multivibrators 9 and 10. The diffraction unit 11, the generator of 12 pulses, the generator of 13 followers of pulses and the control unit 14. The device works as follows. The video signal with reference pulses is fed to the input of video amplifier 1, from the output of which the video signal is fed to the first input of the first element I 2, to the second input of which gates are sent from the output of the first multivibrator 9. The second multivibrator 10 is triggered by synchronizing pulses and generates a pulse differentiated by a differentiating unit A falling edge starts the generator 12. From the output of the generator 12, pulses of adjustable duration are fed to the input of the generator 13 and to the input of the first of the multivibrator 9 which forms the gate pulses lasting longer than the duration of the pulse frames. The frame pulses are allocated by the first element 2 and arrive at the first input of the second element 3, the second input of which at certain times receives switching pulses from the output of control unit 14. Thus, at the output of the second element And 3, the selected reference pulses will take place only in the presence of switching pulses. From the output of the second element And 3, the pulses of the rappers arrive at the signal inputs of the temporary discriminator 4. The generator 13 is triggered by a pulse of adjustable duration from the output of the generator 12 and produces the next pulses early and late. In the temporary discriminator 4, by comparing the position of the vertical axis of symmetry over the area of the reference pulse with the position of the common front of the following pulses, the left and right parts of the area of the reference pulse coincide with the following impulses, and they are proportional to the areas of voltage that are subtracted. Since the time mismatch of the axis of symmetry of the reference pulses and the position of the common front of the following pulses is zero, the error signal is zero. Therefore, when the switch 7 is turned on and the execution unit 6 is connected to the current regulator 8, the axis of the latter in the circuit of the centering rollers of the diverting system in the corresponding channel of the meter remains in the same position, which corresponds to the operating current with accurate alignment of images in the central zone. In the absence of a test table, during camera operation, when the alignment of the raster of the transmitting tubes is disturbed, the position of the vertical axis of symmetry of the reference pulse on the edge of the raster relative to the common front of the following impulses changes and a temporary mismatch occurs. In this case, the areas of the left and right parts of the frame of the reference frame are not equal, and when subtracting proportional voltages, an error signal is created, which from the output of the temporary discriminator 4 through the power amplifier 5 goes to the executive unit 6, which rotates the axis of the current regulator 8 the coils of the deflecting system and automatically adjusting the amount of current until the raster of the transmitting tube is set to the foremost position. Thus, in the proposed device, the accuracy of alignment does not depend on the nonidentity of coordinate distortions on the edges of the rasters in different channels of the camera, which is achieved by individually adjusting the position of the total. of the front of the following pulses relative to the vertical axis of symmetry of the frame pulses for each channel. Apparatus of the Invention A device for centering a raster horizontally of a transmitting television tube, comprising a series-connected video amplifier and an element, to the second input of which is connected the output of the first multivibrator, whose input is connected to the input of a servo pulse generator, to the output of which are connected in series a temporal discriminator, power amplifier and executive unit, current controller and serially connected second multivibrator whose input is a sync pulse input The differential unit is characterized by the fact that, in order to improve the accuracy of centering, an impulse generator, a switch, a second AND element and a control unit are introduced, the output of which is connected to the first input of the second AND element, the second input of which is connected to the output of the first AND element , and the output of the second element I is connected to the second input of the temporary discriminator, the switch input is connected to the output of the execution unit, and the switch output is connected to the input of the current regulator, and the generator input of the pulses is connected to the output d ffrentsiruyuschego block and vy.hod connected to inputs of the first multivibrator and the generator follower pulses of information sources, the received note in the examination 1. Copyright certificate USSR № 507958, cl. H 04 N 5/34, July 9, 1976. / F four