SU565259A1 - Digital frequency meter - Google Patents

Description

one

The invention relates to electrical measuring technology and can be used to create frequency meters of continuous action — the following frequency meters.

The following digital frequency meter is known, containing a block of reference frequencies, a frequency analyzer on frequency diuclearizers, keys, a mixer, shift registers, a reset device and a digital indicator 1. However, this frequency meter has a low response rate due to the integrating property of the measuring circuit.

A frequency counter is known that includes a reversible counter, electronic keys, OR logic, a reference frequency generator, a counter divider, a multivibrator, and input triggers of the anti-match 2 circuit.

The aim of the invention is to increase the speed. This is achieved by the fact that a digital frequency meter containing a multivibrator, two input triggers, a counter divider whose outputs are connected via electronic keys to the inputs of a multi-input OR circuit, and the input is connected to the output of an input trigger connected to the output of a reference frequency generator, a reversible counter, the outputs of which are connected to the second inputs of electronic switches, one input is connected to the outputs of the multi-input OR circuit, the other through the OR circuit - with the output

The second input trigger is equipped with comparison elements, an AND circuit, two triggers and an additional counter divider. The last input is connected to the output of the multivibrator and the input of the AND circuit, two outputs are connected to the inputs of input triggers, and the third is connected to the input of a trigger, the second input of which is connected to the output of the second input trigger and the input of the reference element, and

output - to the second input of the circuit I, the third input connected to the output of the second trigger. Moreover, the second input of the comparison element is connected to the input of the reversible counter, its output is connected to the input of the second trigger, the second

the input of which is connected to the third input of the reversible counter.

The drawing shows a block diagram of a digital frequency meter comprising a reversible counter 1 with binary bits 2,

electronic switches 3, counter divider 4 with output bits 5, multi-input circuit OR 6, comparison node 7, counter divider 8 with intermediate bits 9 and last trigger 10, triggers II and 12, circuit OR 13; And 14, the multivibrator 15, the reference frequency generator 16 and the input triggers 17 and 18.

The frequency meter works as follows. With the help of the pulse “Setting O”, the reversible counter 1 is set to “About, and

the trigger 12 supplies the circuit 14 and the first of the two potentials that open the circuit. With the arrival of a measured frequency pulse, the trigger, and applies to circuit 14 a second potential, opening circuit 14. At this moment, a set of frequency pulses / o of multivibrator 15 arrives at the WI.NU of the reversing counter 1. intermediate bit 9, since the beginning of the patch coincides with the initial state of all intermediate bits 9, and its end with the moment the selected bit 9 is turned on (trigger 11 is turned off at this moment), and therefore the circuit 14 is turned off. Thus, at each entrance th pulse frequency measured by the counter in reversion .NY enters Lachko pulses.

The burst pulses recorded in the reversing counter open the keys 3 and through the circuit OR 6, the feedback frequency pulses f sample from the output bits 5 of the counter divider 4 to the reversible counting bus, to which the pulses come from the reference generator 16. The larger the number recorded in the reversible counter, the greater the number of keys 3 opened, the higher the frequency of the feedback. A moment will come when the frequency of the feedback is compared with / i, the trigger is turned on, the circuit 14 is closed, a number directly proportional to f meas is recorded in the reversible counter. The operation of the triggers 17 and 18 of the anti-coincidence circuit provides the phase shift of the pulse sequences (' s) and / w matte the width of the switching period of the trigger 10, thereby eliminating the phase superimposition of these frequencies and the failure of the reversible counter.

Claims (2)

Invention Formula A digital frequency meter containing a multivibrator, two input triggers, a counter divider, the outputs of which are connected via electronic keys to the inputs of a multi-input circuit OR, and the input is connected to the output of an input trigger connected to the output of the reference frequency generator, a reversible counter whose outputs are connected to the second inputs of electronic keys, one input is connected to the output of an MN input circuit OR, the other input through the OR circuit to the output of a second input trigger, characterized in that, in order to increase speed, it entered comparing element AND circuit, a trigger and two additional COUNTING divider having an input connected to the output of the multivibrator and the input of And, the two outputs are connected to the inputs of input triggers, the third is connected to the input of the trigger, the second input of which is connected to the output of the second input trigger and to the input of the reference element, and the output to the second the input of the circuit I, the third input connected to the output of the second trigger, the second input of the comparison element connected to the input of the reversible counter, its output to the input of the second trigger, the second input of which is connected to the third input of the reversible counter. Sources of information taken into account during the examination 1. USSR author's certificate No. 250308, cl. G 01R 23/00, 1965. 2. USSR author's certificate number 393693, cl. G 01R 23/00, 1972 (prototype).