SU1356258A1 - Device for checking transmission section of broadcasting videography system - Google Patents

Abstract

This invention relates to automation. The purpose of the invention is to improve the accuracy of control. The control unit contains r-1 pulses, a display unit 2, a video signal generator 3, a clock r 4, r-signal 5 service pulses, a switch 6, a shift register 7, a television signal generator 8, a mixer 9, a modulator 10 , rr 11 carrier frequency, character generator 12, block 13 comparison of codes, block 14 of permanent memory (BS1), block 15 of counters, block 16, computed O5 o sd 00

Description

SRI (BV) of the given number of failures, histogram shaper 17 and buffer register (BR) 18, Mixer signal 9, which is a complete television signal with teletext data in the frame interval mixed with it (using switch 6 and mr 5) of the damping pulse, is subjected to amplitude modulation and is fed through the communication channel 30 of the broadcast television to the receiver 19 of the teletext. The result of the comparison, two bit code combinations (the reference of the SPT 14 and recovered from the real

one

The invention relates to automation and can be used to measure and control the noise immunity of a broadcast video system, quickly adjust the clock frequency of the additional information signal transmission and quickly evaluate the reliability of signals received by the broadcast video decoder.

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

The drawing shows a structural electrical circuit of the device. control of the transmission path of the broadcasting videography system and the block diagram of the teletext receiver. .

The control unit of the transmission path of the broadcast video system includes a pulse generator 1, a display unit 2, a video signal generator 3, a clock generator 4, a service pulse generator 5, a switch 6, a shift register 7, a television signal generator 8, a mixer 9, a modulator 10, a generator 11 carrier frequency, character generator 12, block 13 of code comparison, block 14 of constant memory, block 15 of counters, block 16 for calculating the reduced number of faults, shaper 17 histograms and buffer register 18, Receiver 19 of teletext soda INH kinescope 20, video amplifier 21, a demodulator 22, clock selector 23, the block 24 teletext isolation.

A broadcast television signal by the receiver 19) is recorded and fed to the BV 16, where the maximum number of disruptions in the discharge and the normalization of the results of failures in other bits relative to the maximum occur. Then, using the imager 17, which qualitatively displays the results of the control, as well as using the BR 18, the character generator 12 and the imager 3, a display of quantitative measurement data is obtained on the screen of the display unit 2, 1 slug.

a read generator 25, a code converter 26, a decoding unit 27, a RAM block 28 and a character generator 29 "The drawing also shows

the same communication channel 30.

The device works as follows.

The clock generator 4 synchronizes the operation of the generator 5 service pulses, the shift register 7, the imager 8 of the television signal, and also from its output to the input of the pulse generator 1 a signal of the clock frequency of teletext. From the output generator 1 of the pulses, a parallel discharge (binary) code (for the BCH code used in the USSR with a counter-parity equal to 16) is then fed to switch 6, which serves as

shivan to the teletext signal of the servant chips (bit and byte synchronization, packet number signal, etc.,) generated by the generator 5 service impulses. The sequence of code combinations thus formed is fed to the shift register 7, which is a parallel code converter, into a serial one. Output

the shift register 7 teletext signal is fed to the input of the mixer 9, to the other input of which the video signal from the output of the imager 8 of the television signal. Output signal

mixer 9 is the full television signal with the replacement

data of teletext in it in the intervape of a frame extinguishing pulse. This signal is modulated by a modulator 10 and a carrier frequency generator 11, which is subjected to amplitude modulation by a high frequency signal and fed to a communication channel 30 of a broadcast television. The signal is then fed to the input of the demodulator 22, which is the input to the teletext receiver 19. The sync pulse selector 23 selects the gating of the teletext data, i.e. the selection of those lines in the frame extinguishing frame in which the additional information signal is transmitted. This and gating pulses start up the readout generator 25, which controls the permanent memory unit 14 of the monitoring device, which stores precisely the information currently generated by the pulse generator 1. The code combinations obtained by the teletext extraction unit 24, through the code converter 26, which converts a serial binary code into a parallel binary code, go to decoding unit 27, where error detection and correction takes place, and from its output group, the code combination is written memory Graphic display of bit code combinations takes place on the screen of the kinescope 20 of the receiver 19 teletext through character generator 29 and video amplifier 21. Two bits of code combinations (reference from fixed memory unit 14 and reconstructed from a real broadcast television signal by teletext receiver 19 coming from block 28 memory is compared using block 13 comparison of codes, the result of comparison, in this case: the number of failures in bits, recorded by block 15 of counters and fed into block 16 of the reduced number of failures, where the maximum number of failures in the discharge occurs and the results of failures in other bits relative to the maximum are normalized. By means of the histogram 17

Order 5814/56 Edition 636

Prod. polygons pr-tie, Uzhgorod, st. Project, 4

Claims (2)

displaying the results of the control, as well as using the buffer register 18, the character generator 12 and the video signal generator 3, the display of quantitative measurement data is obtained on the screen of the block 2. The formula of the invention A transmission path monitoring device for a broadcast video system comprising a pulse generator, a carrier frequency generator, a shift register, a display unit, serially connected code comparison unit and counter block and serially connected clock generator, television signal generator, mixer and modulator whose output is output device, the other input of which is connected to the output of the carrier frequency generator, one output of the clock generator through the shift register is connected to another input from mixer, and another output connected to the input of the pulse generator, aphid. In order to improve the accuracy of control, a fixed memory block, a histogram generator, a serially connected service pulse generator and a switch, a serially connected calculator of the reduced number of failures are entered , the buffer register, the character generator and the video signal generator, the output of which is connected to the input of the display unit, and the other input through the histogram generator is connected to the other outputs of the calculation unit of the given number of faults, the inputs of which are connected to the corresponding outputs of the counter block, the outputs of the fixed memory block are connected to the corresponding inputs of the code comparison block, the other inputs of which are the first inputs of the device, the second inputs of which are the inputs of the fixed memory block , the outputs of the pulse generator are connected to the corresponding other inputs of the switch, the outputs of which are connected to other corresponding inputs of the shift register, and the output of the clock generator is connected to the input of the gene service pulse generator Subscription