SU152001A1 - Device for measuring the ratio of the signal magnitude to the magnitude of the fluctuation disturbance - Google Patents

Description

DEVICE FOR MEASURING THE RELATION OF THE SIGNAL VALUE TO THE VALUE OF FLUCTUATED INTERFACE

It was dated July 24, 1961, No. 739393 / 26-9

to the Committee on Inventions and Discoveries at the Council of Ministers of the USSR Published in «Bulletin of inventions No. 23 for 1962

Apparatus is known for measuring pulsed fluctuations in estimating a normal distribution curve using various analyzers and counters. However, measurements using known devices are complex, and the results obtained are subjective, since they depend on the art of the operator.

A distinctive feature of the proposed device for measuring the ratio of the signal magnitude to the magnitude of the fluctuation disturbance is the presence of two channels. One channel contains a calibrated pulse generator and attenuator, another limiter and switched filters for alternately measuring the level of the test signal and interference on an oscilloscope. A photoelectric converter with a slot opening parallel to the scan axis is installed in front of the oscilloscope screen. Such an embodiment of the device simplifies the measurement process and allows a direct reading of the desired signal ratio to the effective interference value.

FIG. 1 is a block diagram of an apparatus for measuring the ratio of a signal magnitude to a magnitude of a fluctuation disturbance using an oscilloscope; in fig. 2 - oscillograms of test signals with fluctuation disturbances superimposed on them.

The principle of operation of the device is as follows. The test signals (with superimposed fluctuations of noise on them) are fed to the input 2 of device 3. For better observation of interference, the upper part of the signal is limited and amplified by a cascade 4. From the output of the transmitter signal 5, the attenuation characteristic of which takes into account the features of visual interference disturbance, last 152001 - 2 -

blunt to the input of the oscilloscope 6, and the lowpass filter 7 is bypassed. A slit 8 of a photomultiplier 9 is installed parallel to the horizontal scanning line in front of the center of the oscilloscope screen.

By vertical alignment of the waveform before slit 8, the maximum reading of instrument 10 is achieved, and then, for example, by adjusting the sensitivity of the latter, its arrow is set at a division of 100%. After that, phased symmetric rectangular pulses // from generator 72 are supplied to the input of the oscilloscope 6 or to the input 2 of the device 3 (in the case of measuring low levels of fluctuation noise). The magnitude of these pulses is continuously changed by the attenuator 13 until the level of the oscillogram is reduced to up to 60% of the maximum level (first count by attenuator 13). In this case, the middle part of the waveform is shifted from position 14 to position 15. The pulse amplitude corresponding to this moment is equal to the effective voltage U., f of the fluctuation disturbance, since the amplitude distribution of the disturbances in the video signals and, consequently, the strength of the oscillogram are subject to the normal law.

Then cascade 4 and. the weighing filter 5 is turned off and the low-pass filter 7 is turned on, releasing the signal from the high-frequency interference components. The oscilloscope observes a signal 1, on which calibrated rectangular voltage pulses ip-effect are superimposed. Gradually outputting the attenuation of a calibrated attenuator 13, a curve 16 is obtained, the rectangular pulses of which are equal to the test signal / (second count by attenuator 13).

The difference in readings on the attenuator corresponds to the magnitude of the fluctuation disturbance:

f 201og - / (db),

where and c is the voltage of the signal between control levels (black and white), i.e., the target value.

F ,. , f 201og Y + 6db.

Subject invention

A device for measuring the ratio of the signal magnitude to the magnitude of the fluctuation disturbance using an oscilloscope, on the oscillogram of which the magnitudes of the disturbance and signal are determined, characterized in that, in order to simplify the measurement process and obtain a direct reference of the sought signal ratio to the effective disturbance value, one of which contains a generator and attenuator of calibrated pulses, and the other a limiter and switched filters for alternately measuring the level of the test signal and bottles on the oscilloscope screen in front of which is mounted with a photoelectric converter slotted hole parallel to the scan axis.

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