SU781897A1 - Device for protecting single-cycle reproduction amplifier of magnetic recording apparatus - Google Patents

Description

one

The invention relates to instrument engineering and can be used in digital magnetic recording techniques for reproducing information from magnetic media, in particular from magnetic cards.

The use of digital magnetic recording devices in universal magnetic heads with separated recording and playback windings reveals the need to protect the input amplifier circuit from the EMF arising at the ends of the playback winding during the recording process.

A protection device for an amplifier of reproduction is known, which contains a L-shaped quadrupole is, in the longitudinal arm of which a resistor is connected, and in the transverse connected two counter diodes two diodes.

The disadvantage of this device is the substantial power dissipation of the write amplifier at the indicated resistor, as well as the increased value of the output resistance of the magnetic head in the playback mode.

It is also known to protect a single-ended reproduction amplifier of a magnetic recording apparatus containing resistors and diodes, the first of which is connected via an anode and cathode respectively between the first output terminal and the second output terminal of the device formed by a common bias source bus, the second end of which is connected resistors connected by the second ends respectively to the cathode of the third diode and the anode of the third diode. The circuit of this device is one of the arms of the symmetric scheme used to protect two-wire amplifiers; reproduction, and provides insignificant losses of the recording amplifier on its elements

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However, with an increase in the number of reproduction cycles of the recorded waveform. its quality characteristics deteriorate due to the flow of bias through the reproduction winding, which contributes to the partial decompression and magnification of the waveform and, therefore, the signal-to-noise ratio. The invention of the invention is an increase in the number of reproduction cycles without degrading the kawfiCTBeHHfiix characteristics of the waveform. . The goal is achieved by the addition of quarters and a diode to the device, while the third cathode and the anode of the first DIODE are interconnected to form the first input terminal of the device, and the second input clip is formed by the jBToporqKWffla resistor and cathode of the second diode, the second diode and fourth anode The diode, the cathode of which is connected to the anode of the third diode, is connected, interconnected and connected to the common busbar, and the junction. Offset .. The drawing shows a diagram of the proposed device. -;:. , ;;. :: -: -; -v The device contains two resistors 1 and 2 and four diodes 3-6. The first diode 3 of the anode and cathode is connected respectively between the first and this {these are the terminals 7 and 8 of the device output. The output 8 terminal is formed by a common bias source bus, the second bus is connected to the first ends of resistors 1 and 2, the second terminals of which are connected to the cathode of diode 4 and anode of diode 5. The cathode of diode 5 and the anode of diode 3 are connected together and The first zero terminal 9 of the device is 9, and the second terminal 10 of the input is formed by the connection point of the second end of the resistor 1 with the cathode of diode 4. The anodes of diode 4 and diode 6, the cathode of which is attached and the anode of diode 5, are interconnected and are connected to a common busbar bias source . The device works as follows.,, W. The winding of the universal universal telephone is connected to the device so that when recording the impulse on the first terminal 9 of the input HWeef tusc o is negative, and the second terminal 10 is positive polarity of the signal. This signal locks the diode 4, preventing power dissipation by increasing the ay element of the device. At the same time, the voltage at terminals -7 and 8 of the output device does not exceed the voltage drop on diodes 5 and 6. At the end of the imyulsa ayisy, the polarity of the signal received by the driver.

781897 A positive surge generated by the magnetic head is shunted by diode 3, the voltage drop on which determines the voltage value at terminals 7 and 8 of the device output. In playback mode & bias current through the playback winding does not flow, due to the formation of equipotential points between the second ends of the resistors 1 and 2. At the same time, the diodes 5 and 6 do not shunt the play winding,. since diode 5 is closed, since it is connected between these points. The reproducible signal from the first input terminal 9 pushes to the first terminal 7 output yes-directly, and from the second input terminal 10 to the second output terminal 8 through the current opened by the bias flowing through the resistor 1, diode 4.. , . . The use of the invention makes it possible to preserve to a great extent the qualitative records of the recorded information in. the process of its repeated reproduction and, in addition, simplifies the manufacturing technology of blocks of magnetic heads, thanks to the possibility of using single-ended amplifiers. works. Formula of the invention Device for protection of a single-stage reproduction amplifier of an N-unit recorder, containing resistors and diodes, the first of which is connected via an anode and cathode respectively between the first output terminal and the second output terminal of the Device, the second which bus is connected to the first ends of the resistors connected by the second ends of the cooTBetCTBeHHo to the cathode of the second diode and the anode of the third diode, characterized in that, in order to increase the number of reproduction cycles without deterioration and the quality characteristics of the sound recordings, an additional four-diode diode is inserted into the device, the ka, the third and the first diode diodes are interconnected and form the first input terminal of the device, and the input terminal is formed by the second rd connection point of the diode and cathode, the second diode and the fourth The diode whose cathode is connected to the anode)

The third diode is interconnected and connected to the common bus of the mixing source.

Sources of information taken into account in the examination

1, Blocks of functional units, computer MIR-. Technical specification, Mashpriborintorg, no. 16, p. 34

2k Ryzhkov, V.A., et al. External magnetic storage devices on magnetic media, Moscow, Energie, 1978, p. 202.

Claims (2)

Formula ³⁵ A device for protecting a single-cycle playback amplifier of a Magnetic Recording apparatus, containing resistors and diodes, the first of which is connected between the anode and cathode, respectively ^! output terminals and the second output terminal of the Device formed by the common Bus of the bias source, the second bus of which is connected to the first ends of the resistors connected by the second ends to the cathode of the second diode and the anode of the third diode, respectively, that in order to increase the number of playback cycles without compromising the quality characteristics of ¹ signalogram, an additional fourth diode is introduced into the device, while each third and anode of the first diode are connected together and form the first input terminal of the device two, and the second input terminal is formed by the connection point of the second end of the resistor and the cathode of the second diode, the anodes of the second diode and the fourth diode, the cathode of which is connected to the anode of the third diode, are interconnected and connected to a common bus of the bias source. Sources of Information taken into account in the examination 1. Blocks of functional units, computer 'MIR-2 *. Technical description. VO 'Mashpriborintorg *, No. 16, p. 34. 2 ·. Ryzhkov V.A. et al. External memory in a magnetic carrier, M., 'Energy *, 1978, p. 202.