SU1145489A1 - Device for selection of television scan line signal - Google Patents

Abstract

A TELEVISION LINE SIGNAL DEVICE, containing serially connected sync selector, field pulse selector and field selector, the outputs of which through the first switch are connected to the input of the row selector, the output of which is connected to the input of the selector pulse former, the output of which is the device output, and shaper horizontal sync pulses, g - the input of which is connected to the output of the sync selector, and the output to the second input of the block for selecting the floor, which is different from the fact that Fundamentals of functionality by allowing the signals of two adjacent lines in one field and three adjacent lines in a frame to be enabled, a field frequency pulse divider by two, a blocking pulse driver, an And element, and a second switch, the field pulse frequency divider by two connected to the first output of the field selector; output to the input of the blocking pulse generator V), the output of which is connected to the first input of the element I through the second switch, It is connected to the second input of the row selection unit, and the output of the horizontal sync pulse generator is connected to the second input of the second switch and to the second SP input of the element I.

Description

The invention relates to television and can be used in apparatus for measuring parameters of television systems. A device for selecting a television line signal is known, comprising a serially connected sync selector, a field selection block, a delay block, a trigger, an And element, a blocking pulse generator and a selector delay block, a second sync selector output is connected to the second inputs of the And element and the selector block. the second output of the blocking pulse generator is soicinep with the second input of trigger I. This device characterizes, with insufficient stability, the selection of the selected line and limited functional The possibilities are due to the fact that the device extracts the signal of only one selected line. The closest to the invention to the technical essence is a device for separating the signal of a television line containing sequentially connected sync selector. the field pulse selector and the field selection unit, the outputs of which are connected via the first mode selector switch to the input of the row selector unit, the output of which is connected to the generator of a selector pulse, the output of which is the device output, and the second input is connected to the second input of the field selector unit and with the output of the horizontal sync pulse maker, the input of which is connected to the output of the sync selector 2. The disadvantages of the known device are the limited functionality associated with the inability to select two a trok in one field, or three lines in a frame. The aim of the invention is to expand the functionality of the device for the selection of a television line signal by ensuring that the signals of two adjacent lines in one field and three adjacent lines in a box are selected. This goal is achieved by the fact that the device for the separation of the signal of the television line. containing a serially connected sync selector, a field pulse selector and a field selection block whose outputs through a first switch are connected to an input of a row selection block whose output is connected to an input of a selector pulse generator whose output is an output of the device, as well as a horizontal sync driver that has an input connected with the output of the sync selector, and the output with the second input of the field selection block, a field frequency pulse divider for two is inserted, a blocking pulse shaper, element And and the second switch, the input of the splitter of the field pulse frequency for two is connected to the first output of the field selection block, the output to the input of the blocking pulse generator, the output of which is connected to the first input of the element I whose output is connected to the second the input of the row selection unit, and the output of the horizontal sync pulse maker is connected to the second input of the second switch and to the second input of the element I. In FIG. 1 is a block diagram of a device for extracting a signal from a television line; FIG. 2 - time diagrams that show his work. The device for selecting a television line signal contains a sync selector 1, a field pulse selector 2, a field selection block 3, a row selection block 4, a selector pulse shaper 5, a horizontal sync pulse shaper 6, the first switch 7, a field pulse frequency divider 8 two shaper. 9 blocking pulses, the element And 10 and the second switch 11. The device for the selection of the signal of the television line works as follows. The sync selector 1 selects a sync mixture arriving at its input, from which the selector 2 zero pulses and the shaper 6 horizontal sync pulses select the corresponding frame (Fig. 2a) and lowercase (Fig. 25) sync pulses.

arriving at the inputs of the block 3 selection of the floor. On the first, second, and third outputs of the field selection block 3, odd (pulses, 2c), even (Fig. 2d), and both (Fig. 2a) fields are generated, respectively. These pulses through the first switch 7 are fed to the first (installation) input of the row selector 4, the second input of which receives the lower-case sync impulses from the output of the element 10. At the I position of the second switch 11, the row selector 4 after each pulse to its first input generates at the output a pulse (Fig. 2 3), which coincides with the K-m horizontal sync pulse (K is the number of the allotted string in the field). In this case, the operation of the device does not differ from that of the prototype, and the output (depending on the position of the first switch 7) separates the signal from one line of an odd field, one line of an even field, or a signal of two adjacent / lines of fuzzy and even field.

In position II of the second switch 1.1, the device operates as follows.

From the first output of the field selection block 3, the odd-field clock pulses (Fig. 2c) are fed to the input of the divider 8 of the field pulse frequency by two, the signal from the output of which (Fig. 2e) starts the blocking device 9 of the blocking pulses, the output pulses of which (Fig. 2e) prohibit the passage through the element And one line sync pulse in every second odd field of the frame (Fig. 2g). As a result, in the T position of the first switch 7, the K-th and K + 1-st lines of one frame floor form at the output of the device, a single-line signal of the even fourth field of the frame is generated at position II, and the K-th signals at position III. and K + 1 st lines of odd floor and located between them the K-th line of even floor.

Thus, the proposed device with respect to the prototype has wider functional capabilities, which makes it possible to perform a number of additional measurements in the vertical direction of a television raster, for example, to evaluate the quality of interlaced scanning.

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Claims (1)

DEVICE FOR SELECTING A TELEVISION LINE SIGNAL, comprising a sequentially connected sync selector, a field pulse selector and a field selection unit, the outputs of which are connected through the first switch to the input of the line selection unit, the output of which is connected to the input of the selector pulse generator, the output of which is the device output, as well as the former horizontal sync pulses. the input of which is connected to the output of the sync selector, and the output is connected to the second input of the field selection unit, which is characterized by the fact that, in order to expand the functionality by providing the possibility of amplification of signals of two adjacent lines in one field and three adjacent lines in a frame, a repetition rate divider is introduced field pulses by two, a blocking pulse shaper, an And element, and a second switch, the input of the field pulse divider being two connected to the first output of the field selection block, the output with the shaper input I have blocking pulses, the output of which through the second switch is connected to the first input of the And element, the output of which is connected to the second input of the line selection block, and the output of the horizontal sync pulse generator is connected to the second input of the second switch and to the second input of the element I. Fig 1