SU743020A1 - Magnetic recording and reproducing apparatus - Google Patents

Description

I

The device relates to the field of equipment, namely, the equipment of the vE network recording.

The magnetic recording path, in effect, has a limited amplitude-frequency characteristic, depending on the speed of movement of the carrier and the resultant level of the production technology of the heads and tapes.

In turn, the carrier dvizheniya speed is limited, since its increase reduces the operational reliability of magnetic recording apparatus. At present, for accurate magnetic recording, the speed of movement of the carrier does not exceed 608 cm / s.

In this connection, the problem of increasing the maximum frequency of the recorded pulses at. This rate of movement of the tape and the specific quality of the magnetic heads and tapes is very relevant.

Magnetic recording and reproducing devices are known in which the initial pulse sequence is converted into H recordable pulse sequences, the pulse frequency in which is K times lower than the original. Each of the / C sequences is recorded on a separate lane Cl3.

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In magnetic recording, the frequency of the recorded pulse sequence is chosen so that the recording-reproduction path only skips its first harmonic, which ensures the recording of the pulse of the maximum frequency sequence.

In this case, the magnitude of the signal, and therefore the signal-to-noise ratio at the output of the playback amplifier, is determined by the amplitude of the first harmonic and is inversely proportional to the frequency of the recorded pulses.

Amshtudah harmonics - maximum, ifJi JL / V 2

de d / - the duty cycle of the pulse sequence.

From the formula it follows that the optimal rate of pulse duty ratio of the recorded sequence is two.

The pulse rate of the pulses in the initial sequence is always greater than unity. The drawback of the device is that the pulse ratio in each of the recorded C sequences is (times higher, higher than the original, and therefore higher than the optimum, as a result of which the maximum recording frequency: sent pulses at a given signal-to-noise ratio playback amplifier is below the maximum possible.:.

The most typical of the technical entity to the present invention is a magnetic recording and playback device containing a trigger, a recording amplifier, a first recording head connected in series, as well as a second recording head, the OR circuit of which is connected in series to the first input and a first reproduction amplifier; and a second reproduction head connected in series and a second reproduction amplifier f2j to the second input.

The disadvantages of this device include an insufficiently high maximum frequency of the recorded pulses at a given signal-to-noise ratio due to the trans- portability of the recorded, pulses over the optimal / V-2.

The purpose of the invention is to increase the maximum frequency of recorded pulses.

The goal is achieved in the Map Recording and Playback device, between the trigger input and the second recording head there are additionally connected in series the NOT circuit trigger recording amplifier, and between the output of each playback amplifier and the corresponding input of the OR circuit, the serially connected NOT circuit and the AND, the output of the first usalntel playback is connected to the second input of the tamper circuit I, and the output of the second playback amplifier is connected to the second input of the first circuit I.

On fng. 1 shows a functional diagram of the device; in fig. 2 - timing diagrams that show the operation of the circuit.

Magnetic recorder and playback device with impudent r. Trigger 1, NOT circuit 2, trigger 3, amplifiers. 4 and 5 recordings, 6 and 7 recording heads, S and 9 reproduction heads, 10 and 11 reproduction amplifiers, NOT 12 and 13 circuits, AND 14, and 15 circuits, OR circuit 16,

The original pulse sequence is applied to the counting trigger input.

I and the NOT circuit input 2. A pulse sequence from the output of trigger 1, amplified by the amplifier 4 records, goes to the recording head 6 and is written to magnetic media. The initial pulse sequence is inverted from the output of the HE circuit 2 to the counting input of trigger 3, the pulse sequence from the output trigger 3 amplified amplifier 5 records, arrives

: into the recording head 7 and recorded onto magnetic media.

Both recorded sequences are produced by reproduction heads 8 and 9, then amplified and formed by reproduction amplifiers 10 and 11. The first pulse sequence from the output of the playback amplifier 10 is fed to the input of the circuit NOT 12 and to the second input of the circuit 15, the second pulse sequence from the output of the amplifier

II reproduction is fed to the input circuit of the HE 13 and to the second input of the circuit AND 14

The inverted first pulse sequence from the output of the NOT 1 circuit arrives at the first input of the AND 14 circuit. The inverted second pulse sequence from the output of the NOT 13 circuit arrives at the first input of the AND 15 circuit.

The pulse sequences from the outputs of the circuits AND 14 and 15 are fed to the circuit OR 16, at the output of which the initial pulse impulse is formed.

Claims (2)

On FGER. 2 shows the following belt plots: voltage 17 at the input of the recorder; voltage 18 at the output of the trigger 1, amplifier 4 records, amplifier 10 playback, voltage 19 at the output of the circuit NOT 2, voltage 20 at the output of the trigger 3, amplifier B of the recording, amplifier 11 playback, voltage 21 at the output of the circuit NOT 12, pitch 22 at the output of the circuit NOT 13: voltage 23 at the output of the circuit and 14, nap |) married 24 at the output of the circuit 15; voltage 25 at the output of the circuit OR 16. The introduction of additional elements into the recorder and playback allows you to increase the maximum frequently recorded pulses at a given t signal-to-noise ratio at the output of each playback amplifier, due to the fact that the pulse ratio in each of the recorded sequences is optimal and is equal to two. As already noted, the signal-to-noise ratio at the output of the playback amplifier is inversely proportional to the frequency of the recorded pulses. Thus, according to a given relation to the Lyum signal, the frequency of the recorded pulses in this device is V times higher than in the known. Claims of the Invention Magnetic recording and reproducing device comprising a trigger, a recording amplifier, a first recording head, connected in series, and also a recording head , the OR circuit, to the fifth input of which the first playback head and the first amplifier play are connected, and the first amplifier is connected to the second input, and the successively connected second head are connected to the second input. playback and second usi / ttel reproduction, tl and cha; moreover, in order to increase the maximum frequency of recorded pulses, between the trigger input and the second recording head the series-connected HEj trigger, recording amplifier are additionally connected, and between each output the playback amplifier and the corresponding input of the OR circuit are connected in series with the NOT circuit and the AND circuit, while the code of the first amplifier is reproduced connected to the second input of the second AND circuit, and the output of the second amplifier The reproduction is connected with the second input of the first circuit I. Sources of information taken into account during the examination 1. A. V. Goncharov et al. Technique video recording magnets. M., Energie, 1970, p. 28-30. 2. The author of the USSR USSR № 350030, cl. Q 11 B 5/00, 1971. ENZ Hih TG ШЦ.22.