SU1438025A1 - Device for measuring scanning non-linearity of crt - Google Patents

Abstract

The invention relates to a television technique. The purpose of the invention is to simplify the device by eliminating an oscilloscope. The device contains a sync generator 1, a frequency divider (DF) 2 key 3, video amplifier 5, triggers 6.11, sweep block 8, deflector system 9, CRT 10, a block of photovoltage transducers (I1) 13. A mixer 4, to the reversible counter 7, the demultiplexer 12 and the pulse counter 14. Due to the correct selection of the DF 2 dividing ratio and on a CRT screen 10 w as a label. Considering the number of scale marks between the beginning of the line and each of the marks, it is possible to determine the time for an electron beam to pass each interval between adjacent FCs 13 and calculate it using the known coefficients of coefficients. nonlinearity of the CRT 10. 1 Il.

Description

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The invention relates to a technique of television and can be used when measuring the parameters of the beam sweep in cathode ray tubes.

(CRT).

The purpose of the invention is to simplify the device by eliminating an oscilloscope.

The drawing shows the structure-jiaH electrical circuit of the device, i A device for measuring the non-linearity of a CRT scanner contains syncro jrenepaTop 1, divider 2 frequencies, | key 3, mixer 4, video amplifier 5, first trigger 6, reversible counters 7, block 8 sweep, rejecting system 9, CRT 10, second trigger 11, demultiplexer 12, block 13 of photo-converters,: counter 14 pulses.

The device works as follows:

; At its first output, the synchronous cell 1 generates a sync mixture, which synchromes the sweep unit 8, using the deflecting system 9, sweeps the electron beam of the CRT 10, the signal from the second output of the synchronous generator 1 through the mixer 4 excites the input of video amplifier 5, which forms A signal for the intensity of the electron beam of a CRT 10, fipH this over the entire screen of a CRT 10, over a small gap, a white-field signal is generated. The pulses from the output of a block of 13 phototransmitters arrive at the counting input of the counting 14 pulses operating in the subtractive mode. A parallel code is connected to the parallel loading bus of this counter, which corresponds to the number of photoelectric generators in block 13 decremented by one in binary calculation. Loading of this code is produced at the beginning of a row of pulses from the first output of the synchronous generator 1о. When the electron beam runs through the photogenerators of block 13, a pulse appears at the output of the pulse counter 14, which causes the appearance of a pulse at the jiepBoro trigger b, the output of which

iodutuyenny to the input of the demultiplexer 12, allows the passage through it of pulses from the fourth output of the synchronous generator 1 to one of the outputs of the demultipexor; 12, Then

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the next line in each of the reversible counters 7, the number of which is equal to K, will be recorded the number of pulses corresponding to the transit time of the electron beam of the CRT 10 between adjacent photoconverters of block 13. After that, the pulse from the output of the counter 14 pulses overturns the first trigger 6, which causes the passage of impulses through; | emultipexor 1-2 and the appearance of a logical unit at the output of the second trigger II, further prohibits the counting of pulses by the counter 14. After that, in the next frame in the free space of the screen raster A large sampling grid is simulated, since the key 3 at this time connects the output of the divider 2 parts to the input of the mixer 4. In this case, the coefficient of the delegator of the splitter 2 frequencies is chosen close to the number K and such that in cTpo frHOM The period is placed an integer number of pulses formed by the divider 2. Therefore, the large-scale grid of samples on the screen of the CRT 10 will be fixed. After that, the pulse from the third output of the chip generator 1. switches the input of the key 3 to its second output, which is connected to the subtracting input of the reversible counters 7. Due to the correct selection of the division factors of the divider, 2 of the reversible counters 7 form each frequency The line signal that falls on the corresponding 1, C 1 1 input of the mixer 4, appears at its output, and hence on the screen of the CRT 10 in the form of a label. Considering the number of scaled marks between the beginning of the line and each of the marks, you can determine the time of the electron beam of each interval between the neighboring transducers and calculate the HejraneiiHOT ratio of the CRT 10, the pulse front from the third output of the synchro Heater 1 All reversible bills 7 and triggers 6 and 1I reset 33 zero states 1 and the device is again ready to repeat the whole cycle of operation.

Formula I 3 o b e te n n

The device is for measuring the nonlinearity of the scanning of a cathode ray tube containing a frequency divider.

31D38025

a key, two triggers and a synchronous generator, which is connected to (K + 2) -th input, the first output of which is connected to the mixer, and the second output - to the combined input of the scanner, the output of which is connected to the reversing of the key system, the input of the key of the connections with the frequency divider located on the electron beam output, the input of which is a tube (CRT), to the cathode of which the bottom is connected to the fourth output of the syn - key switch of the video amplifier, and the screen of the oscillator and information input of the CRT optically connected to the photo house unit The multiplexer, To the outputs of which converters, is connected to the summing inputs e so that, in order to simplify the corresponding To reversing counters by eliminating oscillators, the Kth pulse counter, the first one, the mixer is inserted, the counters of the second the triggers are connected by a series of pulses, a demultiplexer and K between the first output of the synchronous counters, the outputs of which is the generator and the gating input are connected respectively to the K input counter of the pulses, the setting inputs of the mixer, the output which sub-l No. of which are code inputs to the input of the video amplifier, the photoelectric converters block, the second output of the synchro-generator and the digital input of the pulse counter are connected to the (K + 1) th input of the mixer, the third output of the photo-transducer block sync generator output of the connectors, and the bit outputs are connected to the setup inputs of two flip-flops “to the corresponding address inputs and K. reversible counters and to the control input multiplexer, the gate input to the corresponding input of the key, the first output of which is connected to the output of the first about

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Claims (1)

Claim Device for measuring non-linearity of a scan of a cathode ray tube containing a frequency divider. a key, two triggers and a sync generator, the first output of which is connected to the input of the scan unit, the output of which is connected to a deflecting system located on a cathode ray tube (CRT), to which the output of the video amplifier is connected, and the screen of the CRT is optically connected to the photoconverter unit, distinguishing - The reason is that, in order to simplify the device by eliminating the oscilloscope, a mixer, a pulse counter, a demultiplexer, and K reverse counters are introduced, the outputs of which 15 are connected respectively to K input. I’ll give a mixer, the output of which is connected to the input of the video amplifier, the second output of the clock being connected to the (K + 1) th input of the mixer, 20 the third output of the clock generator! it is connected to the installation inputs of two triggers and K reversible counters and, to the control input of the key, the first output of which is connected to the (K + 2) -th input of the mixer, and the second output - to the combined subtracting inputs K of reversible counters, the key input is connected to the output of the divider frequency, the input of which is connected to th · fourth output syn- ^g hrogeneratora and data input demultiplexer, K outputs which are connected to respective summing inputs of the reversible schetchi'kov K, K-th pulse counter, the first and second flip-flops included afterbirth * between the first output of the sync generator and the gate input of the pulse counter, the setting inputs of which are the code numbers of the photoconverter unit, the even input of the pulse counter is connected to the output of the photoconverter block, and the bit outputs are connected to the corresponding address inputs of the demultiplexer, whose gating input is connected with the release of the first trigger.