SU1578766A1 - Device for checking sound-reproduction apparatus - Google Patents

Abstract

The invention relates to telecommunications. The purpose of the invention is to expand the functionality of the device and its measurement range. The signal of a sound-reproducing unit is converted by a shaper and a single-shot into a sequence of pulses with a specified duration. Using a filter and an amplitude detector, the variable component of the signal is selected, taking into account the temporal instability of the position of the pulses. The registration unit produces an indication of the magnitude of this instability on a logarithmic scale. Due to the precise measurement of a given time interval in a reversible counter, the deviation of the average frequency of rotation of the mechanical units of the sound-reproducing unit from the nominal value is formed. This deviation is indicated by a digital indicator.

Description

The invention relates to means for controlling sound-reproducing apparatus and can be used to measure the non-uniformity of movement of their mechanical components and the deviation of their average rotational speed from the nominal one.

The purpose of the invention is to expand the functionality.

The drawing shows an electrical block diagram of the device.

The device contains a series-connected band-pass filter 1, the input of which is connected to the control output of the sound-reproducing unit 2, shaper 3 pulses, one-shot 4, first low-pass filter 5, amplitude detector 6, comparator 7. second low-pass filter 8 and recording block 9, and also

serially connected pulse generator 10, the first 11 and second 12 pulse frequency dividers, exponential voltage generator 13, the output of which is connected to the second input of the comparator 7, connected in series the first key 14, whose input is connected to the output of the one-vibrator 4, reversible counter 15, register 16 and a digital indicator 17, connected in series by the third divider

18frequency of pulses, the input of which is connected to the output of the first divider 11, element

19 delays, a counter 20 and a second decoder 21, the output of which is connected to the control input of the first key 14, are connected in series to the first decoder 22 and a trigger 23 connected between the output of the reversing counter 15 and its

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a second input 4, the input of which is connected to the output of the first divider.

The device works as follows.

The reference harmonic signal with a frequency of 3150 Hz from the measuring tape or measuring record passes through a noise-canceling band-pass filter 1. In the former 3, pulses are generated with a period of the reproduced signal, each of which the one-shot 4 produces a pulse of a fixed duration. In the first filter 5 with a passband (0.1-4.0 Hz, the signal component corresponding to the measured temporal instability of the motion of the mechanical components of the sound-reproducing unit 2 is extracted. The output signal of the first filter 5 is modulated and averaged in the amplitude detector 6 Simultaneously, the second divider 12 generates pulses, each of which acts on the generator 13, opening the key 25, leads to a charge on the capacity of the storage element 26. When the capacity from the output of the generator 13 is discharged, the input of the comparator 7 enters si exponential drive. When the signal of the amplitude detector 6 becomes less than the signal of the generator 13, the output of the comparator 7 is formed by the level / -or 1. The pulse sequence at the output of the comparator 7 is averaged in the second filter 8 and enters the registration unit 9, the scale of which is graduated This logs the level of detonation of the rotation of the mechanical units of the audio-reproducing unit 2. In this case, the registration of the level of detonation is performed on a logarithmic scale, which expands the measurement range rhenium device relative detonation level.

In addition, the signals from the output of the first divider 11 pass through the second key 24, are counted by a counter 20. Considering that the generator 10 is highly stable, a counter proportional to the current time is generated in the counter 20. When calculating a certain time interval, for example, 3.175 seconds, when the frequency of the pulses at the output of the first divider is 10 kHz, the level of the log is formed at the output of the second decoder 21. H, which closes the first and second keys 14 and 24. Thus, the input of the reversible counter 15 through the key 14 comes in a time interval equal to 3.175 s from the moment the signal is produced by the third divider 18, the corresponding number of pulses from the output

one vibration damper 4. In this case, for each pulse of the third divider 18, the contents of the reversible counter 15 are overwritten into the register 16 for display in

a digital indicator 17 of the average deviation of the rotational speed of the mechanical units from the nominal value. After a small pulse delay in the delay element 19, it is fed to the installation inputs of the counter 20 and the reverse counter 15 and the processes described above are repeated. The first decoder 22 is set to the amount of signal corresponding to the number of pulses generated by the single vibrator 4 during

5 3.175 seconds, provided that they arrive at a nominal frequency. At the same time, the reversible counter first works on subtraction due to the installation of the trigger 23 in the appropriate state by the setting signal with

0 output of delay element 19 Upon reaching a predetermined state of a reversible counter, such as a bullet, decoder 22 generates a log level at its output. T, which flips trigger 23

5 to the opposite state, which puts the reversible counter 15 in the addition mode. Consequently, the digital indicator 17 will like the deviation value of the rotation frequency 1 of the mechanical

0 nodes of the audio reproducing unit 2 of the nominal value.

Claims (1)

Claims A device for controlling sound reproducing equipment, containing successively connected pulse generator and one-shot, as well as a recording unit, characterized in that, in order to expand the functionality of the device by ensuring the measurement of the average offset frequency of rotation of mechanical components from the initial, , the input of which is connected to the output of the sound-reproducing unit, and the output of co5 is united with the input of the pulse shaper, as well as in series nye first lowpass filter, an amplitude detector, a comparator and a second low-pass filter, whose output is connected to the input 0 registration unit, serially connected pulse generator, first pulse frequency divider, second pulse frequency divider and exponential voltage generator, the output of which is connected to the second input of the comparator, serially connected first key, reversible counter, register and digital indicator, serially connected first decoder whose input is connected to the output of the reversible counter. and a trigger, the output of which is co-connected with the LXO reversible counter mode control house, a second key connected in series, a counter and a second decoder, the output of which is connected to the control inputs of the first and second keys, and a series connected third pulse frequency divider whose input is connected with the input of the second key and with the output of the first pulse frequency divider, a delay element whose output is connected to the installation inputs of the reversible counter and the counter and the second trigger input, while the output of the third pulse frequency divider is connected to the control input of the register.