SU892329A1 - Digital frequency meter - Google Patents

Description

one

The device relates to a radio metering technique and can be used for adjusting, developing and testing various radio equipment that requires highly accurate frequency measurement (for example, when determining the average relative frequency variation of reference oscillators, while monitoring gradation and setting the scale of receivers etc.).

Universal electron-counting frequency meters are known that automatically measure the averaged values of the frequency of electrical oscillations, which contain an amplifier driver, a time selector, a frequency divider unit, a pulse generator, and a counter 1.

However, the known device has a low speed.

The closest in technical essence to the invention is

2

a device containing a series of connected frequency divider unit, a strobe pulse shaper, a time selector, a pulse counter, a memory register and an indicator connected in series to the census pulse shaper, an indication time shaper and a main reset shaper, the output of which is connected to the second input of the pulse counter, the second the input of the memory register is connected to the second output of the census 2 pulse generator.

However, the known device has a low speed.

IS

The purpose of the invention is to increase speed.

The goal is achieved by the fact that a digital frequency meter containing series-connected frequency switches, a strobe pulse shaper, a time selector, a pulse counter, a memory register and an indicator are connected in series

census pulse former, indication timer and reset master, the output of which is connected to the second input of the pulse counter, second memory register input connected to the second output of the census pulse former, an AND element connected in series to the RS flip-flop and an additional reset former connected to the input of the frequency dividers and to the second input of the strobe pulse former, the output of the latter is connected to the first input of the And element and to the first input of the RS flip-flop, Torah input of which is connected to the second input of the additional relief shaper and to the output of the main relief shaper, wherein the second element M ahod coupled to an output RS-flip-flop and a pulse counter vtorgm input and output element and connected to the input of the pulse shaper census.

1 shows a diagram of the device; figure 2 - waveforms of his work,

The device contains a time selector 1, a pulse counter 2, a memory register 3, an indicator 4, a strobe pulse shaper 5, a strobe pulse shaper 6, a dither pulse shaper, a time shaper 7 and a drive, a reset shaper, element 19 And and KZ-trigger 11, additional heat sink 12.

The output of the time selector f is connected to the counting & time of the reversible counter 2. Information from the latter is transmitted through register 3 of the memory to indicator C. A continuous input pulse of the measured frequency is fed to one input of the time selector I, the other output of which is connected to the first driver output 5 strobe pulses.

The second output of the pulse shaper 5 pulse generator is connected to the first input of the element 10 and S-ahoy of the trigger 11, the direct output of which is connected to the second input of the element 10, the input of the sign installation of the reversible counter 2 and the first input of the additional shaper 12 of the reset. The output of the latter is connected to the installation inputs of the imager 5 strobe pulses and the block 9 frequency dividers. The output of the element 10 is connected to the generator of the 6 census pulses and the output of the main reset generator 8 is connected to the R input of the trigger 11 and the second input of the additional reset generator 12.

The operation of the device is explained by the oscillograms shown in FIG. 2:

a) output pulses from the block 9 frequency dividers;

b) strobe pulses (with driver 5);

c) direct output of trigger 11;

g) reset pulses additional shaper 12;

5 e) census momentum (with shaper 6);

e) impulse of indication time (with shaper 7) j

g) reset pulses for the 4ipper

0 8The device works as follows.

Shaper 5 generates two strobe pulses (Fig. 26), the first of which determines the operation of the counter.

2 on addition, and the second - on subtraction. At the same time, due to the blocking by the trigger II of the element 10, the driver 6 is switched on after the end of

0 of the second gate.

In the initial state, after the effects of the pulses from the shaper 0 on the trigger 11, the element 10 is closed. At the same time, the signal from trigger 11 opens the addition valves in counter 2. Simultaneously, driver 8 starts driver 12, the output pulse from which brings the frequency divider 9 to the initial state (usually state 9). Output pulses 9 determine the formation of a strobe pulse.

After the end of the first strobe by a negative differential, the trigger 11 overturns the unit state, opens element 10 and gives permission for the counting pulses in block 2 to pass through the subtraction input (the fold valves are closed). With the end of the second gate, the shaper 6 of the census pulses is started through the open element 10. The information from counter 2, equal to the frequency difference, is written to the register

3 and tempered on the indicator k.

Claims (1)

Thus, in each measurement cycle, the proposed device automatically detects the frequency difference, which significantly expands the functionality of the frequency meters. The measurement cycle in the proposed device is equal to tc, t; t; 2c (2) where 1d is the duration of the additional reset pulse (fig.2g), usually trjr t4 "For a known device, this is equivalent to two measurement cycles 2 (, t, H, j .t3) where tg is the processing time of two measurement results, to.p "tj, jy. Usually, t-, 2it (i taul4? Compared with known devices. Formula of Invention Digital frequency meter containing successively connected block of frequency dividers, strobe pulse shaper, time selector, pulse counter, memory register and indicator connected in series through pulse shaper 94 shaper display time and fundamentals Noise shaper, the output of which is connected to the second input of the pulse counter, the second input of the memory register is connected to the second output of the census pulse generator, characterized in that, in order to improve performance, an additional AND-element is added to it, serially connected RS-trigger and additional shaper reset, the output of which is connected to the input of the frequency divider unit and to the second input of the strobe pulse former, the output of the latter is connected to the first input of the And element and to the first input of the RS flip-flop the second input of which is connected to the second input of the additional reset generator and to the output of the main reset generator, while the second input of the And input is connected to the output of the short-circuit trigger and the second input of the pulse counter, and the output of the And element is connected to the input of the overwriting pulse generator. Sources of information taken into account in the examination 1. RS Ermolov, Digital frequency meters. L., Energie, 19732. Equipment for frequency and time measurements. Ed. A.P. Gorshkova, M., Sovetskoye Radio, 197b p.167, 196, fig.6.1 and 6.29.