SU1234778A1 - Device for determining value and sign of difference of two frequencies - Google Patents

Abstract

The invention relates to a pulse and measuring technique. The aim of the invention is to simplify the device and increase its reliability. The device contains pulse formers I and 2, triggers 3, 4 and 5, resistors 6 and 7, capacitors 8 and 9. To increase the reliability of determining the sign of the difference in the case of close frequencies, each direct output of the trigger 3 and 4 included in the channels the magnitude of the difference between the two frequencies is connected via capacitors 8 and 9, respectively, to the setup input R. of its trigger, connected via a common bus resistor. The signal determining the magnitude of the difference between the two frequencies can be removed from any of the outputs of the flip-flops 3 and 4. The flip-flop 5, to which these signals are sent, is set to zero or one state, which determines the sign of the frequency difference. 1 hp f-ly, 3 ill. (L Fi, 1

Description

This invention relates to a measurement technique.

The aim of the invention is to simplify the device.

In order to increase the reliability of determining the sign of the difference in the case of close frequencies, each direct output of both D-flip-flops, included in the channels for determining the difference of two frequencies, is connected via a capacitor to the setup input R of its own T-trigger connected to a common bus through a resistor .

FIG. 1 shows the structural electrical circuit of the device; in fig. 2 and 3 - diagrams of his work.

The device contains pulse shapers 1 and 2, triggers 3, 4 and 5, resistors 6 and 7, capacitors 8 and 9.

The inputs of the two pulse shapers 1 and 2 are connected to the corresponding input sources. The outputs of the formers are cross-connected to the information input 10 and the clock input 11 of the flip-flops 3 and 4. The direct outputs of the flip-flops 3 and 4 are connected via capacitors 8 and 9 to the set inputs R of their flip-flops, and the setting inputs are in turn connected to common bus through resistors 6 and 7. Any of the same outputs of the flip-flops 3 and 4 are connected one to the information 10, and the other to the clock input 11 of the flip-flop 5, which determines the sign of the difference between the two frequencies.

The device works as follows.

in a way. I

Shapers 1 and 2 convert

harmonic signals of input frequencies to pulse voltages (fig.2, i3, ai5), connected in phase to the signals at the input. These pulse sequences arrive simultaneously at the information and clocked inputs of triggers 3 and 4. When the leading edge of the pulse arrives at the clock input 11 and the leading or falling edge of the pulse at information input 10, the trigger retains the zero or one state, if at the previous time The information input was present at zero or one level, respectively (Figures 2 and 3, ft and d), which is explained by the delay in receiving information on input 10

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relative to the front of the clock pulse.

Turning on the RC circuit (8, 9 and 6, 7) between the direct output of the D-trigger and

5 setting input R increases

the switching time of the D-trigger is after the arrival of the front of its clocking pulse. At outputs D-three 3 and 4 pulsed

10 sequences with a signal frequency equal to the frequency difference of the input signals (Fig. 2 and 3,). The signal that determines the magnitude of the difference between the two frequencies can be removed from any of

15 outputs for triggers 3 and 4.

Depending on the ratio of the studied frequencies, the leading edge of the pulses at the output of the trigger 3 either precedes the leading edge of the pulse by

20 of the same name of the trigger output 4 for a time equal to the half-period and the frequency being studied, or lags behind it (Fig. 2, 3, b). Depending on this D-trigger 5, where are these

25, the pulses arrive, set to zero or one state, which determines the sign of the frequency difference.

Claims (2)

1. A device for determining the waveform and the sign of the difference between two frequencies, containing two channels for determining the magnitude of the difference between two frequencies, each of which includes a driver and a D-trigger, and a channel for determining the sign, the difference of two frequencies, characterized in that simplify the device, information and clock inputs D-triggers included in the channels for determining the magnitude of the difference of two frequencies are connected to the inputs of the Formers so that the output of each of the drivers connects to one information input of the D-trigger of one channel and one clock input of the D-trigger of another channel, and one of the same outputs of these D-triggers is connected to the information one, and the other to the clock input of the D-trigger that forms the channel for determining the sign of the difference of two frequencies . 2. The device according to claim 1, which is based on the fact that, in order to increasing the reliability of determining the sign of the difference in the case of close frequencies, each direct output of both 3123A7784 O-triggers included in Canash. To the installation input R of its definition of the difference of two G-triggers, connected with the common frequency, is connected via a capacitor through a resistor.