SU746365A1 - Apparatus for testing and calibrating pulse-modulated oscillation voltage meters - Google Patents

Description

The aim of the invention is to improve the accuracy of calibration and calibration of voltage measuring devices of pulse-modulated oscillations at a voltage level of less than 0.1 V.

 The goal is achieved in that a device comprising a control pulse generator, a pulse-modulated oscillator, a sinusoidal oscillator, a sample voltmeter, a sinusoidal oscillation, and a connecting element for

connection of a calibrated measuring device of the voltage of voltage-modulated oscillations in one section of the transmission line with exemplary

A sinusoidal oscillation meter is equipped with a sinusoidal voltage ratio meter / controlled mixer, generator-hetero. din of sinusoidal oscillations, selective null indicator with compens-; in this case, the input of the meter of the relationship of the voltage of sinusoidal oscillations is connected to the output of the connecting element; the first controlled mixer is connected to the same cross-section of the transmission line as the measuring device. in the voltage of pulse-modulated oscillations; the second input of the controlled mixer is connected to the output of the oscillator-oscillator of sinusoidal oscillations; the third input of the controlled mixer is connected to one generator generator voltage controlled by a pulse qix, the other output of which is connected to the generator input of pulse-modulated oscillations; the output of the controlled mixer is connected to the input of the selective null indicator with a compensator .., ..

The drawing shows the block diagram of the device.

The device contains a generator of 1 pulse-modulated oscillations, a Gonor torus 2 sinusoid: l / oscillations, a measurable measuring device 3 voltages of pulsed modulated oscillations, connected to the connecting cable , controlled mixer 7, oscillator-oscillator 8 sinusoidal oscillations, 9 absorbing pulses, selective null indicator 10 with a compensator. The output of the generator 1 pulsed-modulated oscillations and the output of the generator 2 sinusoidal oscillations of the subconnected (inen to the input of the connecting element 4; The input of the measured measuring device 3 voltage pulsed modulated oscillations, the input of the sample voltmeter. 5 the mixer 7 is connected to the same and the same section of the transfer line 746365

chi using the connecting element 4; the output among 1 | of the element 4 is connected to the input of the meter 6 ratios of sinusoidal voltage; the output of the controlled mixer 7 is connected to the input of the selective null indicator 10 with a customer; the output of the oscillator-heterodyne 8 is connected to the second input of the controlled mixer 7; One output of the generator 9 of control pulses is connected to the third input of the controlled mixer 7, and et-o the other output. connected to the input of the generator 1 pulsed-modulated oscillations.

The device operates as follows, y.

From the generator 1 of pulsed modulated oscillations, a signal of a given carrier frequency, duration and frequency of following, synchronized by the generator of 9 control pulses, is fed to the input of the connecting element 4 and by adjusting the signal level. L set the pointer of the reading device of the measuring device, the voltage of the pulse-modulated oscillations (at the limit of 0.1 V and below) to the test point. By adjusting the oscillator frequency of 8 sinusoidal oscillations, set the difference between the carrier frequency of the pulse-modulated signal and the frequency of the sinusoidal oscillation signal of the generator - heterodyne 8, equal to the intermediate frequency of the selective null indicator 10 with a compensator according to the maximum reading of its reading device. In the controlled mixer 7, the frequency is converted only at the time the control pulse is supplied from the control pulse generator 9 and the pulse modulated signal is sampled, and the amplitude of this sample is recorded by a selective zero-indicator 10 with a compensator. The voltage adjustment of the Compensator is set to zero reading on the selective null indicator 10 with a compensator. Next to the input of the connecting element 4, a signal from the generator 2 sinusoidal oscillations and set its frequency equal to the carrier frequency of the pulse-modulated signal supplied earlier. By adjusting the signal level of the generator of 2 sinusoidal oscillations, the zero value of the reading unit of the village of the null indicator 10 with a compensator is set again, and the signal level is measured with a voltage ratio meter 6. sinusoidal oscillations. Then set the voltage level of the generator. 2 sinusoidal oscillations equal to, for example, 1 V, using a diffraction voltmeter 5 sinusoidal oscillations (it is advisable to choose a voltage level of 1 V or more, i.e., where the highest accuracy of the exemplary voltmeter 5 sinusoidal oscillations), then register again signal level by measuring the relationship of sinusoidal voltage with fluctuations. Thus, the actual value of the voltage (Ug) arriving at a reliable measuring device of the voltage of the pulse-modulated oscillations at the limit from;. i ,. 0.1 V and, below, determined from the expression J, Do

 N where UQ is the reference volt reading. . a) meters of sinusoidal oscillations, research institutes, for example 1B; 5 N is the value of the ratio of the voltage of the scientific research institute according to the meter of the relationship of the voltage of sinusoidal oscillations.

The error of calibration and calibration of 20 measuring devices of the voltage of pulse-modulated oscillations (at a limit of 0.1 V and below) by this device is determined by the error of a wave break; a meter of 25 sinusoidal oscillations (at a voltage level of 1 V and more) , the error of the meter of the relationship of the voltage of sinusoidal oscillations, the error of comparison of the amplitude 30 voltages of the samples of the signals to them. pulse-modulated and sinusoidal oscillations. The error of an exemplary voltmeter of sinusoidal oscillations operating in a high-frequency range up to frequencies (up to 100-300), with a voltage level of 1 V and above, is 0.05 -. Dissolution of the sinusoidal voltage ratio meter (for a ratio of 60–70 dB, which corresponds to 1 mV relative to 1–3 V) in a wide frequency range (up to 100 300 MHz) for instruments of higher accuracy (p- These values are between 0.1 and 0.2%. The error in comparing the amplitude voltages of a sample of 45 signals from pulse-modulated and sinusoidal oscillations is purely random and does not exceed 0.05%, as the frequency of the signal of sinusoidal oscillations and the frequency of the pulse-modulated oscillation signal is equal, equal ovy duration samples of both signals, and equal to the amplitude of the voltage at the input samples controlled mixer $ 5.

The device allows to increase the accuracy of the check. and graduations meter 746365

yctjx) actfi voltage and pulse-modulated oscillations (at the limit of 0.1 V and lower) are no less than an order of magnitude compared to known devices.

Claims (1)

1. GOST 16951-71 Pulse electronic voltmeters with a switch. Methods and means of verification. 2, USSR Copyright Certificate 441535r. e 01 R 35/00, 1971 (prototype) .i