SU864176A1 - Device for checking non-uniformity of amplitude-frequency signals - Google Patents

Description

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The invention relates to instrumentation technology and can be used to automatically control amplitude-frequency characteristics (AFC) of filters and other four-terminal networks.

A control device is known in which the frequency of the input signal is varied with the aid of a kasudara generator. At the output of the test object, the maximum and minimum values of the frequency response are recorded using measuring devices, and then the unevenness coefficient 1 is calculated.

However, this device has 15 high complexity and low speed.

It is also known a device containing a generating frequency 20 connected through a control object to one comparator input, the output of which is connected to the first differentiating circuit and to the inverter connected in series and the second differential circuit 25, and one comparator input connected to the serially connected maximum meter, signal values and a divider, for example, but whose output is associated with one. thirty

input block stall connected

output to the indicator 2.

The purpose of the invention is to increase the speed of the device.

Claims (1)

The goal is achieved by the fact that a device containing a oscillating frequency generator, connected, through a control object, to one input of a capacitor, the output of which is connected to the first differentiating circuit and to series-connected inverters and a second differentiating circuit, one input of the comparator connected to series-connected The maximum value of the signal and the voltage divider, the output of which is connected to one input of the unit, are compared with two peak values, compared to the output connected to the indicator. eters, a second comparison block, a trigger, an additional inverter, four: coincidence elements and four keys r, while the inputs of the first and second keys are connected to one input of the comparator, and to the inputs of these keys, respectively, the first and second peaks are also connected dark: to the inputs of the third and fourth keys, as well as to the first and second inputs of the comparison unit, the output of the latter is connected to one input of the first meeting element and with an additional inverter whose output is connected to The first input of the match element, the output connected to the first input of the trigger, connected by the second input to the code of the first match element, while the direct output of the trigger is connected to one input of the third match element and to the control inputs of the first and third keys, the inverse model is mentioned The first trigger is connected to one input of the fourth elec- talent of the match and with the control inputs of the second and fourth keys, the outputs of the third and fourth elements of the same match are connected to the reset inputs of the first and peak detectors, the output of the third and fourth keys are connected to another input of the first comparison unit, the output of the first differentiating circuit is connected to other inputs of the first and matching elements, the output of the second differentiating circuit is connected to other inputs of the third and fourth elements of the match, the other input of the comparator is connected to the ground bus. The drawing shows the block diagram of the device. The device contains a control object 1, a frequency generator 2 connected to one of the control object 1, a meter 3 maximum signal, two peak detectors 4 and 5, a voltage divider 6, two blocks 7 and 8, four keys 9-12, two inverters: 3 and 14, four elements 15–18 coincide, a comparator 19, two differential circuits 20 and 21, a light 22 and a trigger 23. The device works as follows. The generator 2 generates at the input of the controlled object 1 signal in the desired frequency range. At the exit of this object 1 it is possible to change the amplitude of the signal U,. depending on the frequency. The signal from the output of the controlled object 1 is fed to the meter 3, which remembers the maximum value of the signal, and to the input of the comparator 19 ,. which generates square pulses when the signal passes through the zero level. In addition, the signal from the input signal of the monitored object is fed through keys 9 and 11 to the inputs of peak detectors 4 and 5, only one of the keys 9 and 11 is open depending on the state trigger 23. The state of trigger 23 is determined by block 8, to the input of which the outputs of peak detectors are connected, and the transition of trigger 23 from one state to another can only occur by a signal from differentiating circuit 20 through elements 15 and 16. Differentiating circuit 20 for formulas ruet signal at the moment when the controlled voltage through the zero level, i.e. when the process of storing the peak value of the signal in one of the peak detectors 4 and 5 is completed. The trigger 23 controls the keys 9 and 11 in such a way that the key is closed at the input of the peak detector which measured the current minimum amplitude of the signal, while block 7, the signal arrives one of the keys 10 and 12, and that of the keys 10 and 12 is open at the input of which there is: a lower neck voltage of the peak detectors 4. and 5. Thus, the peak detector, in which the lower peak voltage is remembered, operates in the information storage mode. At the same time, another peak detector is in update mode. The previous information is reset in it by a signal from the differentiating circuit 21 through one of the elements 17 and 18 before starting to store the new amplitude of the monitored signal. If the newly memorized peak value of the signal turned out to be less than the signal stored in the other peak detector, then flip-flop 23 is triggered and the peak detectors 4 and 5 are switched, the peak detector that was in the information storage mode goes into its No. 1 assembly mode, and the other peak detector goes into storage mode. Thus, the current minimum peak value of the monitored signal is memorized in the peak detector operating in the 1-pane information mode. Next, on the input of block 7, on the one hand, the voltage from cxeivBs of the meter 3, through the divider b, and on the other hand - the current minimum peak value from keys 10 or 12. If the ratio of maximum and minimum voltages exceeds the allowable. block 7, a malfunction appears, which is supplied to the indicator 22. The admissible irregularity of the frequency response is set by the magnitude of the transfer coefficient of the divider 6. AFC spine requires only a single pass frequency band. Apparatus of the Invention A device for controlling the amplitude-frequency non-uniformity