SU1285380A1 - Oscilloscopic meter of amplitude parameters of electric signals - Google Patents

Abstract

The invention relates to a radio measuring technique and can be used to accelerate the speed of oscillographic measurements of the amplitude characteristics of a signal. The purpose of the invention, an increase in measurement accuracy, is achieved by reducing the mutual drift of signal images and zero potential. For this purpose, an adder 7, elements AND 16 and 17, elements OR 14 and 18, a digital-analog converter 12 and an analog-digital converter 15 are additionally entered into the device. In addition, the device contains a key 1, an amplifier 2 vertical deflection, switches 3 and 9 , end amplifier 4, cathode ray tube 5, synchronizer 6, sweep blocks 8 and 13, horizontal deflection amplifier 10, control block 11, backlight amplifier 19. The control unit is executed on a microprocessor, a clock generator, memory modules of the decoder, a key and an interface, I hc. f-ly, 3 ill. with (L

Description

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The invention relates to a radar measurement technique and can be used to increase the speed of oscillographic measurements of the amplitude characteristics of a signal. five

The purpose of the invention is to increase the measurement accuracy by reducing the mutual drift of the signal images and the zero potential.

FIG. 1 shows the structure of the proposed oscillographic meter measuring the amplitude parameters of electrical signals; in fig. 2 is a block diagram of the control unit; in fig. 3 shows voltage diagrams at characteristic points of the device; a - the form of the input (studied) signal; B - at the first output of the first scanner; B - on

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first ol lk i p.ruu.ip 1-i and. Yervyyy output of the first B.Pokl 8 pYa: 1vvertiki connected to the first input of the second switch 9, the output KOTOpoi o through the horizontal deviation amplifier 10 is connected to the horizontal deflection of the electron beam tube 5. The first input of the adder 7 is connected to the third output of the amplifier 2 vertical deflection and the second input - with the output of the digital-to-analog converter 12. The input of the control unit P is connected to the output of the analog-digital converter 15; The first output of the control unit 11 is connected to the control input of the key 1, and the second output is connected to the input of the digital-to-analog converter 12. The third and fourth outputs of the control unit 11 are connected to the first output of the first expansion unit and the second input of the first element; 1 - at the output of the first element And; a - at the first output of the second scanner; e - at the output of the second element And; - at the output of the second element OR,

The device contains keys 1, vertical deflection amplifier 2, first switch 3, terminal amplifier 4, cathode-ray tube 5, synchronizer 6, adder 7, first sweep unit 8, second switch 9, horizontal deflection amplifier 10, control block 11, digital-analog converter 12, the second scanner unit, the first element OR 14, the analog-digital converter 15, the first element AND 16, the second element AND 17, the second element OR 18 and the amplifier 19 of the backlight.

The control unit 11 contains a microprocessor 20, a clock pulse generator 21, a random access memory unit 22, a persistent storage unit 23, a decoder 24, a key 25, and an inter- 26.

The first input of key 1 is connected to the bus of the signal under study, and the second input is connected to the common bus. The output of the key 1 is connected to the input of the amplifier 2 vertical deflection, the first output of which is connected to the first input of the first switch 3. The output of the first switch 3 through the terminal amplifier 4 is connected to the vertical deflecting plates of the cathode ray tube 5. The second output of the amplifier 2 vertical deflection through the synchronizer 6 is connected to the input

first ol lk i p.ruu.ip 1-i and. Yervyyy output of the first B.Pokl 8 pYa: 1vvertiki connected to the first input of the second switch 9, the output KOTOpoi o through the horizontal deviation amplifier 10 is connected to the horizontal deflection of the electron beam tube 5. The first input of the adder 7 is connected to the third output of the amplifier 2 vertical deflection and the second input - with the output of the digital-to-analog converter 12. The input of the control unit P is connected to the output of the analog-digital converter 15; The first output of the control unit 11 is connected to the control input of the key 1, and the second output is connected to the input of the digital-to-analog converter 12. The third and fourth outputs of the control unit 11 are connected to the first and second inputs of the first element

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And 16, respectively, and the fifth output - to the second input of the first element OR 14. The information and address outputs of the microprocessor 20 are connected to the corresponding inputs of the operational storage unit 22, the persistent storage 6j; oKa 23, the decoder 24 and the interface 26. Output microprocessor 20 is connected to

the corresponding inputs of the operative storage unit 22 and interface 26, and the Read output, to the corresponding inputs of the permanent storage unit 23 and interface 26. 5 The first and second outputs of the generator 21 clock pulses are connected to the first and second touch inputs of the microprocessor 20, respectively. The first and second outputs of the decoder 24 are connected to the control inputs of the operational storage unit 22 and

constant storage unit 23, respectively. The third output of the decoder 24 is connected to the first control input of the interface 26. The second control input of the interface 26 is connected to the output of the key 25, the other output of which is connected to the common bus. The second information input of the interface 26 is connected to the input of the control unit 11, and the information output, the first, second and third control inputs, to the second, first, third and fifth outputs of the block. 11 controls respectively. The fourth output of the control unit 11 is connected to the third output of the generator 21 clock pulses.

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The device works as follows.

Investigate a signal, for example, in the form of rectangular pulses superimposed on a DC component of a signal, affects the input of the device. After the passage of the key 1, the amplifier 2 (Fig. 3a) is amplified by the vertical deflection amplifier 2, passes through the first switch 3 and the final amplifier 4, and enters the vertically deflecting plates of the cathode ray tube 5. At the same time, the synchronizer 6 forms signals from coming from the second output of the amplifier 2 vertical deflection, synchronization pulses, triggering the first sweep unit 8. The sawtooth signals {fig., 3,6), generated by the first sweep unit 8, pass through the second switch 9, are amplified by the horizontal deflection amplifier 10 and act on the horizontal deflection plates of the cathode ray tube 5. The image signal is illuminated for periods of time corresponding to The motion of the sweep (Fig. 3b), carried out by the first sweep unit 8, is produced by amplifying square pulses from the second output of the first sweep unit 8. These pulses through the second element OR 18 arrive. At the input of the amplifier. 19, the illumination and the output exer affect the modulator of the cathode ray tube 5. As a result, the waveform image is observed on the screen of the tube 5. At the same time, the first, third and fifth outputs of the control unit 11 are set to a logical zero, which affects the control inputs of the key 1, the first switch 3 (via the first element OR 14) and the second commute is the potential of the common bus. The value of this noTeHUHajra after passing the vertical power amplifier 2 and the first switch 3 5 is converted into a constant voltage corresponding to the output stage of switch 3. This voltage is fed to the input of the analog-to-digital converter 15 and digitally O code X on its output is read by the microprocessor 20 in the control unit 11. The reading occurs through the second information input of the interface 26 and is stored in the operational 5 storage unit 22. In this case, the value of the signal offset on the screen of the tube 5 along the vertical is taken into account in the measured value.

Then, the fifth output of control unit 11 of the control unit receives a logic level 1, which through the first element OR 14 acts on the control input of the first switch 3 and connects its output voltage from output 25 and adder 7. This voltage is equal to the sum of two the components are the voltage of the corresponding vertical displacement of the image on the CRT screen (from the third output of the amplifier 2 is the vertical 30 deviation), and the voltage from the output of the digital-to-analog converter 12. The digital code Y obtained as a result of the conversion of the output voltage P 3 the first- switch 35 analog-to-digital converter 1 is read by microprocessor 20 and compared with the previous conversion code X. If Y is X, then the Z code stored in the operational memory 40 of the block 22 and fed to the input of the digital-analog preamplifier 12 via the information output of the interface 26 is reduced. If, then the Z code is incremented. New Z value

mutator 9 (through the first element 16) em to a digital-to-analogue transfer — Microprocessor 20 periodically reader 12 and the output voltage accumulates through the interface 26 a key signal

Read 25 and check its value, the wie-stop terminates when the signal of the key 25 is equal to the voltage of the logical zero. In this case, the control unit 11, in accordance with the program residing in the permanent storage unit 23, outputs a logical voltage 1 to its first output. It arrives at the control input of the key 1, this signal switches the latter to the position at which his exit

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Matora 7 through the first switch 3 acts on the input of the analog-digital converter .15. The digital code at its output is read by the microprocessor 20, after which the operation

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comparison and code changes are repeated until the ratio is satisfied. In this case, the process of determining the code Z is terminated. In this case, a constant voltage equal to a constant voltage is applied to the second input of the first switch 3.

there is a potential shared bus. The value of this noTeHUHajra after the passage of the force dip 2 of the vertical deflection and the first switch 3. converted to a constant voltage corresponding to the output stage mode of the switch 3. This voltage is fed to the input of the analog-to-digital converter 15 and the digital code X at its output is read by the microprocessor 20 in the control unit 11. The reading takes place through the second information input of the interface 26 and is stored in the operational storage unit 22. In this case, the measured value takes into account the amount of signal displacement on the screen of the tube 5 vertically.

Then the fifth output of the control unit 11 receives a logic level 1, which through the first element OR 14 acts on the control input of the first switch 3 and connects to its output voltage from the output of adder 7. This voltage is equal to the sum of two voltage - the voltage corresponding to the vertical displacement of the image on the CRT screen (from the third output of the amplifier 2 vertical deflection), and the voltage from the output of the digital-to-analog converter 12. The digital code Y obtained as a result of the conversion of the output voltage first switch 3 analog-to-digital converter 15 is read by the microprocessor 20 and compared with the previous conversion code X. If Y is X, then the Z code stored in the operational storage unit 22 and fed to the input of the digital to analog preamplifier 12 via the information output of the interface 26 is reduced. If, then the Z code is incremented. The new value of Z is fed to the digital-to-analog converter 12 and the output voltage sum0

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Matora 7 through the first switch 3 acts on the input of the analog-digital converter .15. The digital code at its output is read by the microprocessor 20, after which the operation

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comparison and code changes are repeated until the ratio is satisfied. In this case, the process of determining the code Z is terminated. At the same time on the second entrance of the first room. Mutator 3 is supplied with a constant voltage equal to the constant voltage at its first input, which corresponds to a zero potential at the output of the amplifier 2 of vertical tilt. This provides on the screen of the tube 5 an image of the line corresponding to the zero potential at the input of the meter. The adder 7 is used so that the position of the image of the variable component of the signal on the screen of the tube 5 relative to the zero line does not depend on the vertical displacement of the image.

In the next step of the program, the control unit 1I sets the logic level at its first and fifth outputs, and the logic level 1 at the third output. At the same time, key 1 passes the input signal under study (first input of key 1) to its output. The pulses of the oscillator 21 clock pulses from the fourth output of the control unit 11 pass through the first element AND 16 (Fig. 3, d) and start the second scanner unit 13 (Fig. 3, tt). At the same time, the voltage from the output of the adder 7 is connected through the first switch 3 to the input of the terminal amplifier 4, and the sawtooth voltage from the first output of the second sweep unit 13 through the second switch 9 to the input of the horizontal deviation amplifier 10.

In the pauses between the pulses of the clock generator, the first switch 3 and the second switch 9 return to their initial state, i.e. a vertical deflection amplifier 2 signal and a signal of the first scanning unit 8 are passed to their outputs, respectively.

At the output of the second element And 17, a pulse sequence is formed, the duration of which is determined by the duration of the forward stroke pulse of the second scanning unit 13 (Fig. 3, e). This pulse sequence through the second element OR 18 and the illumination amplifier 19 performs illumination of the beam on the screen of the cathode ray tube 5 not only during the forward stroke of the first rejector unit 8, but also in the time interval when the forward pulse from the first block 8 sweep is absent (Fig. 3, g).

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Thus, the pulse signal from the fourth output of the control unit 1I interrupts the indication of the signal under study at times non-type 5 with the signal, and displays the signal corresponding to the zero potential at the input to the screen of the tube 5. On the screen of the tube 5, at the same time, an image of the investigated

 About signal and zero line in the form of a dotted line. The presence of the adder 7, to the first input of which the bias voltage of the vertical deflection amplifier 2 is applied, allows simultaneously

t5 shift the signal image and the zero line.

Since the image of the signal is periodically interrupted with the frequency of the generator 21 (the fourth output of the control unit 11), due to the non-synchronization of the frequencies of the signal under study and the clock pulses, the image of the signal is fused.

Changing the sweep duration of the second sweep unit 13 allows the number of dotted lines corresponding to the zero line to change.

The microprocessor 20 periodically reads the key 25 signal and checks its value. The reading is stopped when the signal of the key 25 is equal to the voltage of the logical unit, which corresponds to the switch-off considered. . mode. At the same time, the first, third and fifth outputs of the control block 11 receive a logic zero level. This provides an initial state in which the signal under study is displayed without a zero line.

40 The described principle of operation of the device is carried out by periodically accessing the microprocessor 20 (Fig. 2) to a permanent storage unit 23 in which the program of operation of the device is stored. Appeal occurs in the form of setting the address of the current command on the address bus (Fig. 2). In this case, the decoder 24 commands the inclusion of a constant

50 of the storage unit 23. Similarly, the microprocessor 20 is addressed to the operational storage unit 22 and the interface 26.

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Claims (2)

1. Oscillographic meter of amplitude parameters of electrical A halogenop containing a key, the first input of which is connected to the bus of the test signal, the second input to the common bus, and the output to the input of the vertical deflection amplifier, the first output of which through the first switch is connected to the input of the terminal amplifier, the output of which synchronous plates whose input is connected to the second output of the vertical deflection amplifier, and the output through the first scanner to the first input of the second switch, the second input of which is connected to the first output of the second scanner, and the output through the horizontal deflection amplifier. - to the horizontally deflecting plates of the cathode-ray tube an amplifier of the illumination, the output of which is connected to the modulator of the cathode-ray tube, and a control unit, the first output of which is connected to the control input of the key, so as to improve the accuracy measurements for reducing the mutual drift of the signal images and the zero potential, the adder, the first and second elements AND, the first and second elements OR, the digital-to-analog converter, and the analog-to-digital converter, whose input not with the output of the first switch, and output with the input of the control unit, the second output of which is connected to the input of the D / A converter, the third and fourth outputs to the first and second inputs of the first element And, respectively, the output of which is connected to the control input of the second switch, the input of the second scanner, the first input of the first element OR, and the first input of the second element AND, the second input of which is connected to the second output of the second scanner, and the output to the second input of the second element OR the second input of which is the connection to the second output of the generator of the clock pulse output of the first scanner, ow. move with amplifier input podsppe - with the first input of the adder ta 5 0 5 5 0 5 0 five 0 connected to the third output of the vertical decoupling amplifier, the second input to the output of the D / A converter, and the output to the second input of the first switch, the control input of which is connected to the output of the first OR element, the second input of which is connected to the fifth output of the control unit. 2. The meter according to claim 1, characterized in that the control unit comprises a microprocessor, a clock generator, an on-line storage unit, a permanent storage unit, a decoder, an interface and a key, and the information and address outputs of the microprocessor are connected by a bi-directional data bus and the address bus with the corresponding inputs of the operational storage unit, the permanent storage unit, the decoder and the interface, the output Record - with the corresponding inputs of the operational storage unit and the interface, the output H with the inputs of the Permanent Storage Unit and Interface, the first and second clock inputs with the first and second outputs of the clock generator, respectively. The first and second outputs of the decoder are connected to the control inputs of the operational storage unit and the permanent storage block, respectively, and the third output - to the first control input of the interface, the second control input of which is connected to the output of the key, the other output of which is connected to the common bus, the second information input - from the input m of the control unit, and the information output, the first, second and third control outputs are connected to the second, first, third and fifth outputs of the control unit, respectively, the fourth output of which is connected to the third square ppl n lgg ll . m