SU587415A1 - Arrangement for determining four-pole network amplitude-frequency characteristics - Google Patents

Description

The structure of the electrical circuit of the onshore device is described in the drawing.

The device contains a source of a single voltage, a key 2, an integrator 3 with memory, a controlled oscillator 4, a block 5 of measurement and indication, a threshold element b. The figure also shows the measured quadrupole 7.

The principle of operation of the device is as follows.

The threshold element 6 forms a single pulse, the front of which corresponds to the moment of time when the level of the measured signal and jj becomes equal to the reference level (Jgf,, the top is cod and ± ±; is equal to and more decay when

nyfA

Nice Front and Fall of this impulse

And it is differentiated, rectified, and pulses are formed, which are long enough to provide frequency measurement.

Unit 5 of measurement and indication contains a frequency meter and a digital calculator (not specified). The frequency meter is triggered by a pulse from the threshold element. The calculator remembers the measured frequency values and will compute according to the expressions

wed

.

where - the lowest frequency amplitude-frequency

characteristics} f f - higher and medium frequencies

4 | - frequency band.

Measured and calculated frequency values are displayed. The controlled oscillator 4 contains an element (for example, a varicap), with the help of which its frequency is moved by the voltage from the source of the control voltage 1.

At the moment the device is turned on, the DC voltage via switch 2 from the source of control voltage 1 is switched to the integrator with memory 3 and through it to the control of the frequency of the controlled generator 4, the voltage from generator 4c of the FCUjinpX frequency is the control function “ The lowest voltage goes to the measured quadrupole 7, whose signal with a frequency fF (L / 5, np) goes to the powder element 6. The level of this signal is a function of the frequency response of the quadrupole.

The frequency of the signal from controlled oscillator 4 changes as long as the level

and it becomes equal to Ugn, only this will occur, at the output of iiop6roBOi4 of element 6 a first impulse appears, which, having closed the key 2, stops the distance} The first integration of the input voltage.

The memory integrator 3 stores the value of the integrated voltage. At the same time, the controlled generator 4 generates a voltage of a constant frequency. This frequency is the lower boundary frequency f of the quadrupole under study 7. At the same time, the impulse from the threshold element 6 starts the frequency counter in the measurement and display unit 5, which records the frequency value, ..

At the end of the first pulse, the key 2 opens from the threshold element 6, and the voltage on the integrator 3 with memory begins to increase. The frequency of the controlled oscillator 4 starts to change again. When the voltage on the measured quadrupole 7 becomes less, a second pulse appears at the output of the threshold element b. The value of the frequency fg is recorded and measured by this pulse, as well as by the nepBON-ry pulse. In block 5 of measurement and indication, the values of frequencies are memorized in, the values of fcp f are determined

Claims (2)

1. Author's certificate of the USSR N9 296052, G 01 .7 23/14, 26.08.72. 2. The UK patent number 1338533, Kn.G 1 and, 28L1.73.