RU2013994C1 - Pulsooxymeter - Google Patents

Abstract

FIELD: medical equipment. SUBSTANCE: signal from output of current/voltage converter 1 is applied directly to analog-to-digital converter 2. Microcomputer 3 calculates variable component of pulse wave, it also computes degree of saturation of blood by oxygen, accounting with variable and constant components of pulse wave. Light-emitting diode 24 and control circuits 22 and 23 are introduced into the device. LED's flashes are used for observing pulse frequency. Acoustic radiator 27 is introduced into the device, which has control circuits 25 and 26. The radiator radiates intermittent signal, if parameter under control falls outside the limits. EFFECT: improved precision of measurement of degree of saturation of patient's blood by oxygen. 9 dwg

Description

 The invention relates to medical diagnostics and can be used to measure heart rate and oxygen saturation degree of circulating human blood.

 A device is known / manufactured by the Krasnogvardeets production association in Leningrad (see "Combined Indicator Photooxyhemometer" model 057. Technical Description and Operating Instructions dA0.000.057 TO 1978) / which contains a light source / light filters / photocells / amplifier / arrow indicator. This device allows you to measure the degree of blood oxygen saturation of human blood samples and indicates a change in the degree of oxygen saturation of the circulating blood of a person in a hospital.

 However, measuring the degree of blood oxygen saturation with this device is associated with blood sampling / which is painful and unsafe. In addition, this device does not allow you to measure your heart rate.

 Also known device "Pulse Oximeter" (see US patent N 4759369.cl. And 61 V 5/00/1988) / containing a sensor / current-voltage Converter / demultiplexer sampling and storage / two amplifiers / two low-pass filters / ADC / current driver red radiation diode / infrared diode current driver / control generator / seven-segment display / microcomputer / whose output is connected to the display / ADC / diode current conditioners / amplifiers / whose inputs are connected via capacitors to the first and second outputs of the demultiplexer select storage and / input of which is connected to the output of the current-voltage converter / the first and second inputs of which are connected to the anode and cathode of the sensor photodiode respectively / whose first emitting diode is connected to the output of the first diode current driver / second emitting diode is connected to the output of the second diode current driver / input of which is connected to the output of the control generator / inputs and outputs of which are connected to the first diode current driver / demultiplexer of sampling and storage.

This device allows you to measure the pulse rate and the degree of blood oxygen saturation in a patient without taking blood samples / however it has the following disadvantages:
Before digitalization, the signal of the variable and constant component is converted using a demultiplexer for sampling and storing / filter amplifiers from a pulse form into a continuous (analog) signal / which complicates the design. In addition / the transfer coefficient of amplifiers and filters cannot be made exactly the same / therefore, an error will be introduced into the calculation of the degree of oxygen saturation of the blood / which can be avoided / if the signal from the current-voltage converter is supplied directly to the ADC without preliminary amplification and filtering of the variable component of the pulse wave ;
To calculate the degree of blood oxygen saturation on a microcomputer, the value of the constant component of the signal is used (the value of which will depend on the constant component at the output of the current-voltage converter), which can vary with time and temperature. These possible changes are also not taken into account by this technical solution / which leads to additional measurement error;
this technical solution also does not provide for the possibility of visual observation of the patient’s pulse rate and there is no light and sound indication of the excess of the boundary values of the controlled parameter.

 The essence of the proposed technical solution lies in the fact that the pulse wave signal from the current-voltage converter is supplied directly to the ADC / where it is converted to a digital code / and the microcomputer already calculates the value of the variable component of the pulse wave / and the degree of blood oxygen saturation from it. The time intervals between the minima of the pulse wave determine the heart rate. In addition / in the proposed device takes into account the constant bias at the output of the current-voltage Converter.

 An analysis of the known technical solutions showed / that the technical solutions / for which the output of the current-voltage converter is connected directly to the ADC and which take into account the constant component at the output of the current-voltage converter are not detected / therefore, the proposed technical solution has significant differences from the known technical solutions and has novelty .

 In FIG. 1 shows a functional diagram of a pulse oximeter; figure 2 is a functional diagram of a synchronizing generator, figure 3 is a functional diagram of a display unit; figure 4 is a functional diagram of a communication unit with a microcomputer; in Fig. 5 is a functional diagram of a current driver, in Fig. 6 is a functional diagram of a communication unit with a keyboard, in Fig. 7 is a functional diagram of a current pulse generator, in Fig. 8 is a timing diagram at the output of a synchronizing generator; Fig.9-time diagram of the formation of pulses of the currents of the diodes by a synchronizing generator (power sources are not shown).

 The pulse oximeter contains a current-voltage converter 1 / ADC 2 / microcomputer 3 / trunk 4 / first 5 / second 6 current drivers / indicating unit 7 / synchronization generator 8 / sensor 9 / first 10 / second 11 emitting diodes / photodiode 12 / seven switches 13 -19 / communication unit with microcomputer 20 / first register 21 / second register 22 / current impulse driver 23 / LED 24 / circuit 3I 25 / amplifier 26 / sound emitter 27 / communication unit with keyboard 28.

RS-триггеры/ второй 39/ третий 40/ четвертый 41 делители частоты/ пятый 42/ шестой 43 ждущие мультивибраторы/ первый 44/ второй 45/ третий 46 IK-триггеры/ третью 47/ четвертую 48/ пятую 49/ шестую 50 схемы 2И/ третий 51 RS-триггер/ вторую схему ИЛИ 52/ ИМС связи с магистралью данных 53.The clock generator 8 contains a first frequency divider 29 / first 30 / second 31 / third 32 / fourth 33 standby multivibrators / first circuit OR 34 / first 35 and second 36 circuits 2I / first 37 and second 38

RS-triggers / second 39 / third 40 / fourth 41 frequency dividers / fifth 42 / sixth 43 standby multivibrators / first 44 / second 45 / third 46 IK triggers / third 47 / fourth 48 / fifth 49 / sixth 50 circuits 2I / third 51 RS-trigger / second circuit OR 52 / IC communication with the data highway 53.

 The display unit 7 contains the first 54 / second 55 registers / first 56 and second 57 decoders / first 58 / second 59 seven-segment indicators / OR circuit 60 / first 61 / second 62 circuit 2I / first 63 / second 64 keys.

 The communication unit with the microcomputer 20 contains an address register 65 / address decoder 66 / eight circuits 2I 67-74.

 The current driver 5 (6) contains a current amplitude register 75 / DAC 76 / switch 77 / amplifier 78.

 The communication unit with the keyboard 28 contains an IC with three states at the output 79.

 The current pulse generator 23 comprises a standby multivibrator 80 / amplifier 81. The output of the microcomputer 3 through the line 4 is connected to the input of the communication unit with the microcomputer 20 / and the line of the line / via which the reference frequency is transmitted from the microcomputer / is connected to the second input of the synchronizing generator 8 / The first output of the block communication with the microcomputer 20 is connected to the first inputs of the first 5 and second 6 current conditioners / output of the first register 21 / input of the second register 22 / first input of the display unit 7 / output of the communication unit with the keyboard 28. The second output of the communication unit with mic The computer is connected to the eighth input of the communication unit with the keyboard. The third and fourth outputs of the communication unit with the microcomputer 20 are connected to the fifth and sixth input of the display unit 7, respectively / the fifth and sixth outputs are with the first inputs of the first 5 and second 6 current conditioners, respectively / seventh output is with the third input of the synchronizing generator 8 / eighth output is with the fourth input of the synchronizing generator 8 and the third input of the first register 21 / ninth output - with the second input of the second register. The anode and cathode of the photodiode 12 is connected to the first and second inputs of the current-voltage converter 1, respectively / whose output is connected to the third input of the ADC 2 / the second output of which is connected to the first input of the first register 21 / the first and second input of the ADC 2 are connected to the third and fifth outputs synchronization generator 8 / a, the first output of the ADC 2 is connected to the second input of the first register 21 and the first input of the synchronization generator 8 / the first and second outputs of which are connected to the second inputs of the first 5 and second 6 current conditioners. The sixth output of the synchronizing generator 8 is connected to the third input of the 3I 25 circuit / the first input of which is connected to the seventh output of the synchronizing generator 8 and the second input of the indicating unit 7. The second input of the 3I 25 circuit is connected to the output of the indicating unit 7 / and the output through the amplifier 26 is connected to the emitter an audio signal 27 / the third and fourth inputs of the display unit 7 are connected to the second and third outputs of the second register 22, respectively / whose first input is connected to the LED 24 through the current pulse generator 23. The anode and cathode of the first diode 10 s is single with the first and second outputs of the first current driver 5 / anode and the cathode of the second diode 11 is connected to the first and second outputs of the second current converter 6. The first contacts of the switches 13-19 are connected to the GENERAL / second contacts - with the first - seventh inputs of the communication unit with the keyboard 28 respectively.

 The first input of the synchronizing generator 8 is connected to the sync input of the first 45 / second 46 and third 47 IK triggers and the first inputs of the first 36 / second 37 and third 48 circuits 2I / outputs of which are connected to the inputs of the first / second 37 / third 54 RS-triggers / outputs which are connected to the first / second and third inputs of the IC integrated with the data highway 56 / the output of which is connected to the fourth output of the synchronization generator 8 / and the fourth input is connected to the third input of the synchronization generator 8 / the fourth input of which is connected to the R-input of the third RS-trigger and the first input of the second circuit OR 55 / the output of which is connected to the R-inputs of the first 38 and second 39 RS-flip-flops / and the second input - with the output of the third circuit 2I 48 / the second input of which is connected to the inputs of the third 33 and fourth 34 LMW and the output of the fourth 2I 49 circuits / the first input of which is connected to the output of the first IK-trigger 45 / the second input - with IKR inputs of the first IK-trigger 45 and the output of the fifth HMV 43 / whose input is connected to the input of the sixth HMV 44 and the output of the first frequency divider 30 / input which is connected to the second input of the clock generator 8 and the input of the second frequency divider 40 / the output of which is connected to the fifth output of the synchronizing generator 8 and the input of the third frequency divider 41 / the output of which is connected to the sixth output of the synchronizing generator 8 and the input of the fourth frequency divider 42 / the output of which is connected to the seventh output of the synchronizing generator 8 / the first output of which is connected with the second input of the first circuit 2I 36 / input of the first 31 / second 32 LMC and the output of the fifth circuit 2I 50 / whose first input is connected to the output of the fourth LMC 34 and IKR inputs of the second IK trigger 46 / the output of which connected to the second input of the fifth circuit 2I 50. The second output of the clock generator 8 is connected to the second input of the second circuit 2I 37 and the output of the sixth circuit 2I 51 / the first input of which is connected to the output of the first HMV 31 and IKR inputs of the third IK trigger 47 / output which is connected to the second input of the sixth circuit 2I 51. The output of the second HMW 32 of the third HMW 33 and the sixth HMF 44 are connected to the first / second and third inputs of the first circuit OR 35, respectively / the output of which is connected to the third output of the clock generator 8.

 The first input of the indicating unit 7 is connected to the first inputs of the registers 54 and 55 / the second inputs of which are connected to the fifth and sixth inputs of the inputs of the indicating unit 7, respectively / and the outputs are connected to the outputs of the first and second decoders 56 and 57, respectively / the outputs of which are connected to the first inputs of the first 58 and second 59 seven-segment indicators, respectively / whose second inputs are connected to the outputs of the first 63 and second 64 keys / whose first inputs are connected to the power supply of indicators 58 and 59 / and the second inputs of the keys 63 and 64 are connected to the outputs of the first 61 and second 62 of the 2I circuit / whose first inputs are connected to the second input of the indicating unit 7 / the second input of the first circuit 2I 61 is connected to the third input of the indicating unit 7 and the first input of the OR circuit 60 / whose second input is connected to the second input of the second circuit 2I 62 / the fourth input of the display unit 7 / and the output - with the output of the display unit.

 The input of the communication unit with the microcomputer 20 is connected to the address register 65 / the output of which is connected to the input of the address decoder 66 / the first-eighth outputs of which are connected to the first inputs of the first-eighth circuits 2I 67-74 / the outputs of which are connected to the second-ninth outputs of the communication unit with microcomputer 20, respectively / whose first output is connected to the address / data lines of line 4 / the Read line (Input) is connected to the second inputs of the first 67 / sixth 72 / seventh 73 circuit 2I / The Write line (Output) is connected to the second the entrances of the second 68 / third 69 / fourth 70 / fifth 71 / eighth 74 schemes 2I.

 The first input of the current driver 5 is connected to the information input of the current amplitude register 75 / the recording input of which is connected to the third input of the current driver 5 (6) / and the output is connected to the input of the DAC 76 / the output of which is connected to the first input of the electronic switch 77 / the second input of which is connected with GENERAL / the third input is with the second input of the current shaper 5 (6) / and the output is with the input of the amplifier 78 / the first and second output of which are connected to the first and second output of the current shaper 5 (6), respectively.

 The first - seventh inputs of the communication unit with the keyboard 28 are connected to the first-seventh inputs of the integrated circuit with three states at the output 79 / eighth input - with the control input of the integrated circuit with three states at the output 79 / the output of which is connected to the output of the communication unit with the keyboard 28.

 The input of the current pulse shaper 23 is connected to the input of the standby multivibrator 80 / the output of which is connected to the amplifier 81 / the first / second output of which is connected to the first / second output of the current pulse shaper 23, respectively.

The device operates in four modes:
1. The mode of setting the boundary values of the measured parameters.

 2. The mode of monitoring the presence of a finger in the sensor.

 3. The installation mode of the currents of the emitting diodes.

 4. The mode of monitoring the pulse rate and the degree of saturation of blood with oxygen.

 When the power is turned on, the microcomputer 3 enters information in the second register 22 / at which low voltage levels are set at its outputs / information (corresponding to the value of the diode currents) equal to 0/1 of the maximum value is entered into the registers 75 of the first 5 and second 6 current drivers. Next, the microcomputer 3 reads the information from the output of the communication unit with the keyboard 28 and / depending on the state of the switch 13 / the device goes into either the 1st mode of operation / or the 2nd.

A clock generator 8 with a sampling frequency / determined by the first frequency divider 29 generates a time chart in accordance with FIG. In each sample, the ADC 2 performs three voltage conversions from the output of the current-voltage converter to a digital code. The first conversion is performed when / when neither the first 10 / nor the second 11 diodes emit / which corresponds to the measurement of the bias voltage at the output of the current-voltage converter V _t . The second conversion is performed at the moment / when the first diode 10 emits / / which corresponds to the voltage measurement (V _cr ). The third conversion is performed at the moment of radiation of the second diode 11 / which corresponds to the measurement of voltage V _IC . When the contacts of the first switch 13 are closed, the boundary values of the monitored parameters are set / in this case, depending on the position of the switches 14-17, the microcomputer stores the following information from the memory in registers 54/55 of display unit 7:
closed switch 14 - the lower limit value of the heart rate in register 54;
with the switch 15 closed, the upper limit value of the pulse rate is in register 54;
when the switch 16 is closed, the lower boundary value of the degree of blood saturation with oxygen in register 55;
when the switch 17 is closed, the upper boundary value of the degree of saturation of blood with oxygen in the register 55.

 When one of the boundary values of the monitored parameter is highlighted, this boundary value can be changed. When the sixth switch 18 is closed, the limit value increases. When the seventh switch 19 is closed, the limit value decreases. When the contacts of the first switch 13 are opened, the device enters the second mode of operation.

In this mode, the microcomputer 3 enters the information “000” into the first 54 and second 55 registers of the display unit 7 / reads information from the fourth output of the synchronizing generator 8 and if / if the information is 0/01 / which corresponds to / that the first conversion to the ADC has passed 2 / reads and stores the digital code V _t from register 21 / which is written there from the ADC 2 by the signal "End of conversion" and reads the information again from the fourth output of the synchronizing generator 8. When the information becomes equal to "010" / which corresponds to / what happened etc formation voltage V _cr for ADC 2 into digital code and this information is rewritten into register 21 / microcomputer reads it from the first register 21 / stores and reads data again from the fourth output clock generator 8. When the information becomes equal to "100" / which corresponds to / that the result of converting V _ir into a digital code is in the first register 21 / microcomputer 3 reads and stores this information. In this case / if the voltage of the third conversion is greater than 0/95 of the maximum possible conversion voltage / which corresponds to the absence of a finger in the sensor 9 / the device remains in the second mode of operation and the microcomputer continues to read information sequentially from the fourth output of the synchronizing generator 8 and from the output of the first register 21.

 Under the condition / that the voltage read after the third conversion is less than or wounds 0/95 of the maximum possible voltage / which corresponds to / the finger is installed in the sensor 9 / the device goes into the third mode of operation.

 In this mode / reading information from the first register 21 and changing the value of codes / entered in registers 75 of the first 5 and second 6 current conditioners / microcomputer 3 sets the currents / current through the first 10 and second 11 emitting diodes / such that the voltage code / read from the first register 21 after the second and third conversions / corresponded 0 / 75-0 / 8 of the maximum voltage value. After setting the currents, the device enters the fourth mode of operation.

× 100, где S - степень насыщения крови кислородом/ %;
А $\genfrac{}{}{0ex}{}{\text{к}}{\text{1}}$ - коэффициент экстинкции оксигемоглобина на длине волны излучения первого диода 10;
А $\genfrac{}{}{0ex}{}{\text{к}}{\text{2}}$ - коэффициент экстинкции восстановленного гемоглобина на длине волны излучения первого диода 10;
А $\genfrac{}{}{0ex}{}{\text{и}}{\text{1}}$ - коэффициент экстинкции оксигемоглобина на длине волны излучения второго диода 11;
А $\genfrac{}{}{0ex}{}{\text{и}}{\text{2}}$ - коэффициент экстинкции восстановленного гемоглобина на длине волны излучения второго диода 11.In this mode, the microcomputer reads and remembers three values of the voltage codes of each output / from these values, the voltages V are calculated and stored $\genfrac{}{}{0ex}{}{\text{*}}{\text{to}}$ _p = V _cr - V _t , V $\genfrac{}{}{0ex}{}{\text{*}}{\text{and}}$ _k = V _ir - V _t . The microcomputer analyzes the sequence of samples / calculates the amplitude of the variable component of the pulse wave ΔV $\genfrac{}{}{0ex}{}{\text{*}}{\text{to}}$ _p ; ΔV $\genfrac{}{}{0ex}{}{\text{*}}{\text{and}}$ _{to the} resulting as a result of blood modulation of the light flux from the first 10 and second 11 emitting diodes (V $\genfrac{}{}{0ex}{}{\text{*}}{\text{to}}$ _p ; ΔV $\genfrac{}{}{0ex}{}{\text{*}}{\text{and}}$ _{k is} obtained as the difference between the maximum and minimum values of ΔV $\genfrac{}{}{0ex}{}{\text{*}}{\text{to}}$ _p , ΔV $\genfrac{}{}{0ex}{}{\text{*}}{\text{and}}$ _j ) Based on these values, the degree of blood oxygenation is calculated by the formula
S =

× 100, where S is the degree of saturation of blood with oxygen /%;
AND $\genfrac{}{}{0ex}{}{\text{to}}{\text{1}}$ - extinction coefficient of oxyhemoglobin at a radiation wavelength of the first diode 10;
AND $\genfrac{}{}{0ex}{}{\text{to}}{\text{2}}$ - extinction coefficient of the restored hemoglobin at the radiation wavelength of the first diode 10;
AND $\genfrac{}{}{0ex}{}{\text{and}}{\text{1}}$ - extinction coefficient of oxyhemoglobin at the radiation wavelength of the second diode 11;
AND $\genfrac{}{}{0ex}{}{\text{and}}{\text{2}}$ - extinction coefficient of the restored hemoglobin at the radiation wavelength of the second diode 11.

, где

,

- среднее значение постоянной составляющей амплитуды сигналов.α =

where

,

- the average value of the constant component of the amplitude of the signals.

 The calculation of the heart rate is based on the number of samples / resulting between the two minimum values of the pulse wave. The calculated values of the pulse rate and the degree of saturation of blood with oxygen are entered in the registers 54/55, respectively, of the display unit 7. The calculated values of the pulse rate and the degree of saturation of blood with oxygen are also compared by the microcomputer with the previously set boundary values and if they do not go beyond them / at the second and third outputs second register 22 low voltage values are set. When you go beyond the overseas value of the heart rate, a code is written in register 22 / at which a high voltage level is set at its second output / and the information does not change at other outputs. At the same time, a pulsating signal appears on the output of the first circuit 2I 61 of the display unit 7 / which controls the key 63 / turning on and off the seven-segment indicators of the heart rate 58. At the same time, a high voltage level / appears at the output of the OR 60 circuit and at the second input of the 3I 25 circuit 3I 25 circuit appears modulated low frequency / audio signal / which through the amplifier 26 is fed to the emitter of the audio signal 27. When you go beyond the set boundary values of the degree of blood oxygen saturation in the second register 22 records etsya code / wherein the third output register 22 goes high voltage / wherein the other of the second register 22 outputs information does not change. At the output of the second circuit 2I 62 of the indicating unit 7, a pulsating signal appears / which controls the key 64 / turning the seven-segment indicator 59 on and off. At the same time, a high voltage level appears at the output of the OR 60 circuit and at the second input of the 3I 25 circuit. At the output of circuit 3I 25, an audio frequency modulated low frequency signal appears / which, through an amplifier 26, enters the emitter of the audio signal 27.

 Visual monitoring of the pulse rate is as follows. Microcomputer 3 monitors the change in the amplitude of the signal from the output of the first register 21 and at the moment / when the voltage from the third sample reaches the minimum value. which corresponds to the maximum rush of blood in the finger / enters into the register 22 a code / which sets a high voltage level on the first output of the second register 22 / without changing the state of the second and third outputs of this register. In this case, the current driver 23 generates a short current pulse through the LED 24. Thus / by the flashes of the LED 24, you can monitor the pulse rate. Since the LMC 80 of the current pulse shaper 23 is triggered when the signal at its input passes from a low level to a high / then "0" is written to it before writing to the first bit of the second register 22 "1".

 When you remove the finger from the sensor 9, the device goes into the second mode of operation.

 The operation of the synchronizing generator is illustrated by the timing diagrams / shown in Fig.9.

 The communication unit with a microcomputer 20 operates as follows. Signal address / data / control signals CIA / OUTPUT / INPUT, etc. are sent along line 4 / for example, a line of type MPI / etc. By the signal CIA, the address of the device block / to which the microcomputer is accessing is recorded in register 65. This address is decrypted on the decoder 66. Next, the microcomputer sets the input or output signals. At the same time, at the outputs of circuits 2I 65-74 there are signals / by which they are either written from the microcomputer to the corresponding device register / or read from the corresponding device register.

The technical and economic efficiency of the proposed device is / in comparison with the known technical solutions it allows you to:
to simplify the design due to the fact that the device does not use a demultiplexer for sampling and storage / amplifiers and filters;
increase due to the same accuracy in measuring the degree of blood oxygenation;
to expand functionality by introducing an LED and a sound emitter with control circuits / which allows you to visually monitor the heart rate and in case of a controlled parameter exceeding the set limits, signal this by flashing indicators and sound.

Claims (1)

 A PULSE-OXIMETER, comprising a current-voltage converter, an analog-to-digital converter, a microcomputer whose output is connected to the main line, first and second current conditioners, an indication unit containing first and second registers, first and second decoders, first and second seven-segment indicators, the inputs of which are connected with the outputs of the first and second decoders, respectively, whose inputs are connected to the outputs of the first and second registers, respectively, whose inputs are connected to the first inputs of the display unit, synchronizing the first generator containing the frequency divider, the first, second, third and fourth waiting multivibrators, OR circuits, two 2I circuits, two RS flip-flops, the R-inputs of which are combined, and the S-inputs are connected to the output of the first and second circuits 2I, respectively, the first the inputs of which are connected to the first input of the clock generator, the second input of the first circuit 2I is connected to the input of the first and second standby multivibrators and to the first output of the clock generator, the second input of the second circuit 2I is connected to the second output of the clock generator, the third you One of which is connected to the output of the OR circuit, the first input of which is connected to the output of the second standby multivibrator, and the second input of the OR circuit is connected to the output of the third standby multivibrator, the input of which is connected to the input of the fourth standby multivibrator, and the input of the frequency divider is connected to the second input of the synchronizing generator, a sensor containing the first and second emitting diodes of the red and infrared ranges, respectively, a photodiode, anode and cathode of which are connected to the first and second inputs of the current-to-voltage converter respectively, the anode and cathode of the first diode are connected to the first and second outputs of the first current driver, respectively, the anode and cathode of the second diode are connected to the first and second outputs of the second current driver, respectively, the first input of which is connected to the first input of the display unit and the first input of the first current driver the second input of which is connected to the first output of the synchronizing generator, the second output of which is connected to the second input of the second current driver, the third output is with the first input of analog-digital of the second converter, the first output of which is connected to the first input of the synchronizing generator, the second input of which is connected to the main line through which the reference frequency signal is transmitted by the microcomputer, characterized in that, in order to increase the measurement accuracy and expand the functionality, a communication unit is introduced into it with microcomputer, first and second registers, current pulse shaper, LED, ZI circuit, amplifier, sound emitter, communication unit with keyboard, seven switches, in the display unit introduced an OR circuit, two 2I circuits, the first and second keys, the outputs of which are connected to the second inputs of the first and second indicators, respectively, the first inputs are with the power supply of the indicators, the second inputs are with the outputs of the first and second circuits 2I, respectively, the first inputs of which are connected to the second inputs of the display unit, the second input of the first circuit 2I is connected to the third input of the display unit and the first input of the OR circuit, the second input of the second circuit 2I is connected to the fourth input of the display unit and the second input of the OR circuit, the output of which is connected to the display unit, the fifth input of which is connected to the second input of the first register, and the sixth input - with the second input of the second register, the second, third and fourth frequency dividers, the fifth and sixth multivibrators, the first, second and third JK- are additionally introduced into the synchronization generator flip-flops, third, fourth, fifth and sixth circuits 2I, third RS-flip-flop, second OR circuit, communication unit with data highway, the output of which is connected to the fourth output of the synchronizing generator, the first, second and third inputs are connected to the outputs of the tre fifth, first and second RS-flip-flops, respectively, and the fourth input is connected to the third input of the synchronizing generator, the fourth input of which is connected to the R-input of the third RS-trigger and the first input of the second OR circuit, the output of which is connected to the R-inputs of the first and second RS -triggers, and the second input is connected to the S-input of the third RS-trigger and the output of the third 2I circuit, the first input of which is connected to the first inputs of the first and second 2I circuits and the sync inputs of the first, second and third JK triggers and the first input of the synchronizing generator, w The swarm input of the third 2I circuit is connected to the inputs of the third and fourth standby multivibrators and the output of the fourth 2I circuit, the first input of which is connected to the output of the first JK trigger, the second input is with the JKR inputs of the first JK trigger, with the output of the fifth standby multivibrator, the input of which connected to the output of the first frequency divider and through the sixth standby multivibrator to the third input of the first OR circuit, the input of the first frequency divider connected to the input of the second frequency divider, the output of which is connected to the fifth output of the synchronizing gene and the input of the third frequency divider, the output of which is connected to the sixth output of the synchronizing generator and the input of the fourth frequency divider, the output of which is connected to the seventh output of the synchronizing generator, the first output of which is connected to the output of the fifth circuit 2I, the first input of which is connected to the output of the fourth waiting multivibrator and with JKR inputs of the second JK trigger, the second input with the output of the second JK trigger, the second output of the synchronizing generator is connected to the output of the sixth circuit 2I, the first input of which is connected to the first waiting multivibrator with JKR inputs of the third JK trigger, the second input with the output of the third JK trigger, the first contacts of the seven switches connected to a common bus, the second contacts to the first - seventh inputs of the communication unit with the keyboard, the output of which is connected with the first output of the communication unit with the microcomputer, the fourth output of the synchronizing generator, the first input of the first current driver, the output of the first register, the input of the second register, the eighth input with the second output of the communication unit with the microcomputer, the third and fourth outputs which are connected to the fifth and sixth inputs of the display unit, respectively, the fifth and sixth outputs are connected to the third inputs of the first and second current conditioners, respectively, the seventh output is connected to the third input of the synchronizing generator, the fifth output of which is connected to the second input of the analog-to-digital converter, the third input of which connected to the output of the current-voltage converter, the second output to the first input of the first register, the second input of which is connected to the first output of the analog-to-digital converter, and third input - with the fourth input of the synchronizing generator and the eighth output of the communication unit with the microcomputer, the ninth output of which is connected to the second input of the second register, the first output of which is connected via a current pulse shaper with an LED, the second and third outputs of the second register are connected to the third and fourth inputs of the block indications respectively, the second input of which is connected to the seventh output of the synchronizing generator and the first input of the 3I circuit, and the output - with the second input of the 3I circuit, the third input of which is connected to the sixth output the house of the synchronizing generator, and the output through the amplifier is with a sound emitter.

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