SU409159A1 - STAND FOR OBTAINING BENDING READING SIGNALS - Google Patents

Description

one

The invention relates to the field of measuring equipment, namely, to the field of measuring the magnetic parameters of thin-film elements, and can be applied in measuring the magnetic measurements of cylindrical magnetic films with a circular axis of easy magnetization.

The known stand for receiving the envelope of the readout signals contains a current source for a low-frequency magnetic reversal of the magnet film of the entire rod along the axis of the easy magnetizing device, a generator and a magnetizing device, such as a solenoid, for impulsive excitation of the local part of the magnetic film along the axis of the magnetic magnetizing waveform of the sample. , collider of signals, block of synchronous illumination of read signals only on one of the fronts of pulsed read audio, to produce a chain snnhronnoy nizkochastotchiym field n horizontal scanning oscilloscope.

The chickpea envelope finds a wide application for measuring such magnetic parameters of filaments, such as the bevel of the axis of easy magnetization fi, its angular dispersion, as well as the estimation of magnetostriction, etc.

The bevel j is determined by the magnitude of the magnetic field Hv corresponding to the displacement of the point of intersection of the envelope with the field line

relative to the point corresponding to the zero field. The dispersion of light and magnetization is determined by the slope of the curve in the place of its intersection with the floor.

However, the readout signal envelopes obtained using such a bench have a hysteresis. This reduces, and for some classes of eggs, it makes it difficult to quantify the abnormalities of these parameters.

The purpose of the invention is to improve the accuracy of measuring the bevel of the axis of easy magnetization by 3 n of its angular dispersion, as well as the rapid transition from a hysteresis-free envelope to a hysteresis.

This is achieved by including an additional switchable generator in the stand, the input of which is connected to the output of the main generator and the output to the magnetizing device.

FIG. 1 shows a block diagram of the proposed bench; in fig. 2 shows a program of read pulses and read signals that form the observed envelope of the reference signals; in fig. 3 shows a cynical view of the envelope of reading sigals for films with reading with the destruction of information; in fig. 4 - the same, but for plepcs with reading without destroying information.

The proposed stand consists of an electrical circuit (fig, 1), an imprint balaisky circuit designed for low-frequency magnetization of the entire magnetic film 2 deposited on the rod 3 along the axis of light tension. The wipe 3 is included in one of the shoulders of the electric tseni 1, fed from a low-frequency current source (for example, 50 er). Resistors 5 are designed to equalize the current in the shoulders, one of which is a rod 5 with a magnetic film 2, and the other is a drive 6 without a magnetic film.

For pulsed excitation of the local area 7 of the magnetic film 2, a generator 6 and a magnetizing device 9 are provided, made, for example, in the form of a solenoid, along the axis of which passes the rod 3 (the usual length of the solenoid is 1-1.5 mm, the wire diameter is 0.08-0, 1 mm).

The horizontal sweep of the oscilloscope W, intended for observing the envelope}, is carried out synchronously with the variation of the control on the resistor 12, the magnitude of the low-frequency remapping field generated by the current of the source 4. For the synchronization accuracy, the phase-correcting value 13 has been introduced.

For the purpose of observing only the envelope of the readout signals on the oscilloscope screen, a backlight circuit 14 is provided synchronously from generator 8. To isolate the signals from the electrical value 1 and their transducer 15 and amplifier l6, the output of which is connected to the helical input of the oscilloscope 10 .

1 clock 8, together with the additional generator / 7 synchronized from generator 8 by the value of synchronization 18, creates a current pulse program: a read pulse 19 from generator 8 (Fig. 2) with liocrbio, for example, 1 µs with a frequency of newer PS less than 80-100 kHz, and impulse 20 nodgotovkn from geierator / 7. Node pulses must be different from read pulses by no less than 1.2-1.5 times more amnlitud and they have to operate in the gap between pulses 19. Both generators operate on a magnetizing device 9.

Of all the signals read, arising on the fronts of pulses 19 and 20, in the stand form, only the read signal 21 on the leading front of pulses 19 is read.

The characteristic forms of the acquired envelopes Huix 22, 23 and 24, 25 are shown in FIG. 3 and 4.

The stand with the generator turned off 17 is working on the following path, in its own way.

Source 4 causes the izfrequency current to flow through resistors 5, rod 3, and wire 6. Resistor 12 is separated by a voltage that is normal to this current. This arrangement through the phase-correcting chain 13 enters the horizontal input of the oscilloscope.

As a result of the magnetization reversal of the mag H-1t film 2 in the region of the local part 7, and the continuous follow-up of a current pulse of 19 nm from

oscillator 8., not available on NamagpichIvayun1.

The characteristic shape of the envelope for magnetic read-out files is given in FIG. 3 (curve 22); the same for reading files without destroying information - curve 24 (Fig. 4). A characteristic feature of both curve 22 and curve 24 is their large hysteresis.

When the pre-filler generator 17, launched from the generator 8 through the circuit 18, is connected, the current pulses, due to their large amplitude, expand the area of the magnetized magnetic magnet (local area), as a result, the influence of the edge zones (of the magnetic film in the immediate vicinity from the edges of the solenoid) on the formation of the hysteresis of the bending, since the smaller amplitude of the impulse 19 of the contacting provides a zone within the region of the remagiation from the additional pulse of 20 n preparation

Thus, overnight hysteresis-free envelope of readout signals is obtained both for readable films with breaking information (curve 23, fig. 3), and also for readable films without breaking information (curve 25, fig. 4).

The polarity of the additional impulse 20 must coincide with the polarity of impulse 19, because otherwise, because of the richer bevel, the envelope of the reading siyals is shifted to the side, and the opposite coarse skew of I &, i.e., biosyte is a systematic error.

P eedmet and about the and and

A stand for receiving the envelopes of the signals from the measured section of the magnetic braid with a circular axis of lightweight magnetization, containing a current source for the low frequency magnetic reversal of the magnetic film along the axis of the easy magnetization, the generator and the magnetizing device for initiating pulses of the area of the unit to the unit to the unit by the unit. for connecting a rod with a magnetic film, a signal amplifier readout, a unit for synchronous illumination of signals , an electrical circuit for creating a horizontal sweep synchronous with a low-frequency field and an oscilloscope, characterized in that, in order to improve the accuracy of measuring the skew of the easy magnetization axis and its angular dispersion, as well as to quickly switch from a hysteresis-free envelope to a hysteresis, it is equipped with an additional generator that can be switched from which is connected to the output of the main generator, and the output

with magnetizing-1CNM device.

ig1

Q

nineteen

. I /

23

F ,,