SU909688A1 - Reproducing device - Google Patents

Description

(54) PLAYBACK DEVICE The invention relates to a magnetic recording technique, namely, to discrete data playback devices, t Known to a discrete data playback device containing shift registers, phase-locked loops, a reference oscillator, a decoder unit, and a correction unit. The closest in technical essence and the achieved result to the device is a device containing a playback unit, a decoder connected to the output of the playback unit, the first register, whose input is connected to the output of the decoder, the second register of which is connected to the output of the first register, the first decoder, connected with the outputs of the first register, and the output C2. A common drawback of the known devices is the low reliability of their operation, due to failures in the decoding and auto-tuning units. The purpose of the invention is to improve noise immunity. The specified target. is achieved by the fact that the device is equipped with a second drive (a yator, a circuit I. and a trigger whose inputs are connected to the outputs of the descramblers and its output to one of the inputs of the AND circuit, the other input of which is connected to the output of the second register, and to the output bus, when etsm, the inputs of the second gate are connected to the outputs of the second register. The drawing shows a block diagram of the playback device, as well as a block channel circuit of the recording channel. The device contains a synchronization bus 1, bus 2 information, first register 3 entries, block 4 , divider 5, second recording register 6, matching circuit 7, recording block 8, magnetic recording apparatus 9, decoder 10, phase locked loop 11, first reproducing register 12, second reproducing register 13, first decoder 14, second decoder 15 , trigger 16, circuit AND 17, output bus 18 clock pulses and output bus 19 data.

The device works as follows .5

The synchronization and information signals from buses 1 and 2, after being converted in registers 3 and 6 and decoder 8, are provided to magnetic recording apparatus 9. The reproduced signals in the 10 jo decoder are converted into clock pulses AND data pulses.

The pulse data signals from the output of the decoder 10 are fed to the input of the register 12, the sequential entry in which 5 is carried out by clock pulses. Simultaneously with the data recording in the register 12, a code is applied to the inputs of the dehater 14. If this code is a word synchronization code, a pulse is generated at the output of the decoder 20 14, which triggers trigger 16 and the signal from the output of the latter allows the transfer of the Hfr formation from register 13 to the output bus 19. Information transmitted to the output bus 19, accompanied by sync pulses fed to the bus 18 from the block 11 phase-locked loop.

When a sync word is promoted to register 13, a pulse returning trigger 16 is generated at the output of the decipher generator 15 15 to the initial state. Three times from the output of the trigger 16 is closed by the circuit AND 17 and the output of data on pin 19 is prohibited.

In the previous device, in comparison with the known, relaxation elements that are subject to the action of interference are excluded, as a result of which the noise immunity of the device is increased.

Claims (2)

1.Patent of France No. 2103850, cl. G11 B 5 / OO, publ. 1972. 2. US patent number 3792443, cl. 340-172.5, published. 1974 (prototype).