SU1062765A1 - Device for displaying symbols onto crt display screen - Google Patents

Description

The invention relates to teaching aids and tools for training purposes and is intended to display on the oscilloscope screen as a vector diagram of the amma complex amplitudes IQ and C from sinusoidal voltages Uo (t, l Uo5HU) t and U.cltl Uc- ( wi - lsu) ..

Vector diagrams are the most convenient form of representation of currents and voltages in circuits with sinusoidal energy sources for educational purposes. They allow one to imagine the amplitude-phase relations between currents and voltages, and to check Kirchhoff's laws.

A device for displaying vector diagrams is known, comprising an amplitude meter, a phase shift meter and a control unit ij.

The disadvantage of this device is the laboriousness of the process of constructing vector diagrams.

The closest in technical essence to the present invention is a device for displaying vector diagrams on a CRT screen, comprising a master oscillator connected through parallel connected ones. simulated signal drivers with a signal level generator, which is connected through a serially connected, matching unit and a real process signal generator to signal parameter measurements and parameter ratios, a control unit connected to a simulated signal generator, an auxiliary signal generator, connected to a master generator and a unit control unit, and the phase change block of the auxiliary signals connected to the real process signal generator and the auxiliary signals and to the meter of parameter ratios, which contains a series-connected phase discriminator, an integrator, and a threshold unit 21.

The known device allows to obtain amplitude-phase relations between the study of hell and the received signals.

The disadvantages of the known device are low speed and low accuracy of signal reproduction.

The aim of the invention is to increase the speed and accuracy of the device by displaying the dynamic component of the information signal.

The goal is achieved by the fact that a device for displaying vector diagrams on an EL screen containing an amplitude meter and

The phase shift meter, the first and second inputs and outputs of which are the first and second inputs and outputs of the device, a comparison circuit whose input is connected to the input of an amplitude meter, a pulse generator and a mode switch, contains a module selection module whose input is connected to the second input phase shift meter, the adder, the first input — of which is connected to the output of the phase shift meter, the counter, the inputs of which are connected to the outputs of the pulse generator and the mode switch, and the output with the second input of the total Ora, the first switch, the information inputs of which are connected to the outputs of the adder and the counter, and the control input to the output of the comparison circuit, a sine-sinus transducer, the input of which is connected to the output of the ifiepBOro. switch, the second switch, the information inputs of which are connected respectively to the first input of the amplitude meter and to the output of the module allocation node, and the control input to the output of the comparison circuit, and two multipliers, the first inputs of which are connected to the output of the second switch, the second inputs are from the sine-cosine converter outputs, and the outputs are the third and fourth outputs of the device, respectively.

FIG. 1 shows a functional diagram of the device} Fig. Oscillogram of the device; 3, a vector diagram.

The device comprises an amplitude meter 1, a comparison circuit 2, a phase shift meter 3, an adder 4, a counter 5, a first switch 6, a first multiplier 7, a second multiplier 8, a second switch 9, a sine-cosine converter 10, a pulse generator 11 and a mode switch 12, module allocation unit 13

The device works as follows.

The device OS1-5 measures the shift angle of the phase between the input sinusoid voltages UQ) OoS "n () t and iJc (t) Uc- (oot-i 4i), measuring the amplitude values of Ug and DC and mapping to the CRT screen of the complex amplitudes of DO and IJ (in the form of vector diagrams1-1. A vector diagram demonstration, amma, is produced in two modes: static and dynamic

The voltage arriving at the first input of the device is conventionally taken as the reference UQ It) UoS (riQt (Fig. 2, a), and the voltage applied to the second input of the device - signal and U) U (; (ll- ( ((Fig. 2.5)

Meters 1 and 3 measure the amplitudes Do and U and the phase shift iip. The amplitude and phase shift values are displayed on the first and second outputs of the device. Code A (B arrives at the first input of the adder 4, to the second input of which the current phase code is fed (from the output of the counter 5. To the first (net) input of the counter 5, the pulses W are received from the generator 11 pulses. In the static display mode of the fan chart, the counter 5 is zeroed by the zero signal AND from mode switch 12 (4761 01B dynamic mode, the zero signal is removed, as a result, the contents of counter 5 change according to a sawtooth law, simulating a periodic increase in the current phase of the reference signal (from O up to 2n,,. Codes (Check - If) and tf tech are fed to the information inputs of the first switch 6. The control signal of the first switch 6 is formed by the circuit 2 of the comparison according to the law (FIG. 2b) H, with and about It) , with and (tl 0. Therefore, at the output of the first switch 6, the code V ec appears at A S 1 and (, / ffieK-u (f) / pr А 0.) The code C is fed to the input of the sine-cosine converter 10, from the outputs of which the codex3 (and sin C) is fed to the second inputs of the first and second multipliers 7 and 8, respectively. The information inputs of the second; switch 9 are supplied by the voltage jUoi.t) and the first and second inputs of the device and from the output of the allocation module 13. The second switch is switched by the signal A. Thus, during the positive half-periods of the voltage Uo W the first inputs of multipliers 7 and 8 receive a signal U m () (Fig. 2 d), as a result of which voltages are formed at the outputs of multipliers 7 and 8, respectively (Fig. 2, e) U, U W-coscf ,,,, U, j UoU -S4n pTeKDuring negative half-periods of voltage, the signal at the first inputs of the multipliers determined by the expression and m). In this case, the voltages at the outputs of multipliers 7 and 8 are set by the system (Fig. 2, e} (c, -bCf, Uy.Uc (tl-e; n (). From the outputs of multipliers 7 and 8 The signals are supplied to the third and fourth outputs of the device, which correspond to the inputs X and; At the CRT oscilloscope. On the screen of the CRT, during the positive half-periods UQ (t), the vector Qbr is formed, and during the negative periods - to X Og. larger than 20 Hz, the eye does not perceive temporal separation when imaging. In the static mode, the image is stationary, the vector UQ is aligned with the axis OX, the vector and is rotated relative to U by the angle L If clockwise (Fig. 3). In the dynamic mode, both vectors rotate counterclockwise, maintaining the angular mismatch L Cf.

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Claims (1)

A DEVICE FOR DISPLAYING VECTOR DIAGRAMS ON A CRT SCREEN, containing an amplitude meter and a phase meter, the inputs and outputs of which are corresponding to * * but the first and second inputs and outputs of the device, a comparison circuit whose input is connected to the input of the amplitude meter, pulse generator and mode switch , due to the fact that, in order to expand the class of problems to be solved by displaying the amplitude-phase relations of the information signal, it contains a module isolation unit, the input of which is connected to the second the input of the phase shift meter, an adder, the first input of which is connected to the output of the phase shift meter, a counter whose inputs are connected to the outputs of the pulse generator and mode switches, and the output is with the second input of the adder, the first switch, the information inputs of which are connected to the outputs of the adder and counter, and the control input to the output of the comparison circuit, a sine-cosine converter, the input of which is connected to the output of the first switch, the second switch, the information inputs of which are connected respectively to the lane. to the input of the amplitude meter and to the output of the module selection node, and the control input to the output of the comparison circuit, and two multipliers, the first inputs of which are connected to the output of the second switch, the second inputs are with the outputs of the sine-cosine converter, and the outputs are the third and fourth device outputs.