SU720502A1 - Pulse train former - Google Patents

Description

(54) FORMER OF PULSE SEQUENCE

one

The invention relates to a technique of magnetic measurements, namely, devices for monitoring the pulsed magnetic permeability of ferrite cores with PNG.

Pulse sequence drivers are known that are included in the device for controlling cores by the pulse magnetic permeability, containing a generator, a counter, an amplitude calibrator, decipherors 1.

The closest technical solution to the claimed driver is a pulse sequence driver 2. It contains a clock generator, a decimal counter, two descriptors, an And element, a preamplifier and a power amplifier, the clock generator outputs being connected to the inputs of the tenth counter and to the first the inputs of the decoders, respectively, the first output of the decimal counter is connected to the second inputs of the decoders, and the second output of the decimal counter is connected to the third inputs of the decoders, four The entrances of the decoders are combined, the output of the first descrambler is connected to the first and second inputs.

And, and the output of the other decoder is connected to the first preamplifier input, the outputs of the And element are connected to the second and third preamplifier inputs, respectively, the first preamplifier output is connected to the first input of the power amplifier.

The disadvantage of the former pulse trainer is the low accuracy of the measurements, the use of only two pulses of magnetization currents, the need to restructure it when switching the screening of ferrite cores to different temperature regimes, and, as a result, the reliability is low.

The purpose of the proposed invention is to improve reliability. The goal is achieved by the fact that the pulse trainer contains a synchronization unit and two emitter repeaters, the input of the synchronization unit being connected to the output of the decimal counter, and the first output of the synchronization unit is connected to the third and fourth inputs of the AND element the second output of the synchronization unit is connected to the fifth input of the element I, the third output to the sixth input of the element And the fourth output of the synchronization unit is connected to the seventh in One of the elements And to the fifth input of the second decoder, and the second and third outputs of the preamplifier are connected to the inputs of the first and second emitter followers, respectively, the outputs of which are connected respectively to the second and third inputs of the power amplifier.

FIG. 1 shows a block diagram of a pulse trainer. The driver contains a 1 - clock generator, 2 - a decimal counter, 3, 4 - decoders, 5 - a block of decoders, 6 - a synchronization unit, 7 - element I, 8 - a pulse driver, 9 - a preamplifier, 10, 11 - emitter followers , 12 - power amplifier, 13 - thermostat, 14 - measuring resistor, 15 - amplitude regulator, 16 - output jack, 17 - reference-generator switch, 18 - control panel, 19 - amplitude calibrator, 20 - measuring instrument, 21 is a comparator; 22 is a source of reference voltage.

FIG. 2 shows a timing diagram, as shown in Figure 2, and the work of the pulse trainer.

The pulse shaper operates as follows.

After the pulse shaper is turned on into the network with a voltage of 220 V and a frequency of 50 Hz, warming up for 30 minutes, the clock generator 1 begins to generate a pair of pulses with a frequency of 2.5 kHz shifted in time by 10 microseconds (Fig. 2 position 1 and 2) arriving at the inputs of decimal counter 2 and further from its output at the inputs of decoders 3 and 4 of the block of decoders 5 and the synchronization block 6, generating control signals in the following order: control signal (Fig. 2 pos. 6), thanks to which positive and positive current pulses are formed solid polarity, with a positive impulse of magnetic preparation from the output of element 7 of the pulsed imager 8, and a negative pulse from the output of the decoder 4 of the decoder block 5. Behind it with the arrival of control signals Tu1 and Tu2 (Fig. 2 items 8, 9 ) and Tu 2 (Fig. 2, pos. 11) from the synchronization unit 6 to the input of the element And 7 of the pulse former 8, at the output of which pulses of currents of the complete magnetization fields are output (H l, 0j (Fig. 2 pos 10) and a half (H 0.5 e) (fig. 2 pos. 12), going to the input of preamplifier 9, one output of which is connected to power amplifier 12 directly, and the other two through emitter 10, 11, while the emitter follower collectors are connected to the base via a capacitor.

Amplified by power amplifier 12 program pulses, after passing the measuring resistors 14 of the amplitude controller 15, are fed to the sockets "output 16" located on the control panel 18 (Fig. 2 position 14).

To accurately set and measure the amplitude of program pulses, a reference voltage is used, which is generated at stable reference levels. The required value of the reference voltages is set using a comparator 21, to which the reference level of the source 22 is applied, the installation accuracy of which depends on the accuracy class used for measuring the voltmeter 20.

The set reference voltage and the signal from the current pulse shaper are alternately using the switch "reference-generator 17" applied to the measuring resistance of the resistor 14 of the amplitude regulators 15. The equality of these voltages is recorded with great accuracy by the comparator circuit of the calibrator 19, which is made tunnel diode.

The proposed pulse shaper allows:

-increase the stability of the output signal;

- create a sequence of pulses to magnetize the ferrite core with current pulses of a full field, and then with pulses of a half-field current used for operation in pulse transformers;

- with high precision to establish and maintain the currents of the pulse program

- using magnetic preparation pulses to stabilize the magnetic state of the ferrite core with repeated measurements under free conditions and at different temperature conditions;

- make multiple interrogation of the core - 20 times by the field of full current and

10 times the half current field in one measurement cycle;

- set the polling time of one core equal to 84 msec, while magnetizing it with a full field for 56 msec with 140 pulses and a half field for 28 msec 70 pulses;

- generate pulses required for control and synchronization.

The technical and economic effect of the proposed shaper is that it improves the accuracy of setting the currents of the pulse program, the quality of screening the cores with NPG, and increases the productivity.

Claims (2)

1. "Mini-computer for controlling the testing of ferrite cores" Electronics № 19 1970. 2. “Machine for grading cores” Journal “Exchange of experience in the electronic industry No. 1, 1966 (prototype). 1  1G1PPG1G1LG1GTPGiPG1G1GiL  lJLGLPLPnggprlPrlGlnLJLJ