SU769610A2 - Device for compensating for carrier skewness - Google Patents

Description

corresponding one-shot, and the first and second outputs respectively to the additional first and second inputs of the respective sub-registers.

Due to the new set of features, the device fully retains its positive properties — double the amount of possible compensation for the media carrier doubled compared to the prototype while maintaining the accuracy of the reproduced information while increasing the limits of the velocity variation of the carrier. This positive effect has been achieved by introducing new elements into the device, in particular, the skew direction trigger, which allows to have constant information about the skew direction during playback.

The drawing shows a block diagram of the proposed device.

The device contains a gain unit 1, subregisters 2 and 3, one-shot 4 and 5, register 6, resolution block 7, coincidence circuit 8, delay element 9, triggers 10 and 11, delay nodes 12 and 13, and additional resolution blocks 14 and 15.

The device is equipped with elements And 16 and 17, the trigger 18 of the direction of skew and switches 19 and 20.

The elements 16 and 17 are connected between the output of the coincidence circuit 8 and the corresponding setup inputs of the trigger 18. The second inputs of the elements 16 and 17 are connected respectively to the outputs of the single vibrators 4 and 5. The first and second switching inputs of the switches 19 and 20 are connected to the outputs of the trigger 18, respectively. Switching inputs the switch 19 is connected respectively to the main and additional inputs of the single vibrator 4, and the switched inputs of the switch 20 are similar to the outputs of the single vibrator 5. The outputs of the switch 19 are connected to the corresponding additional inputs of subregister 2, and the same outputs of the switch 20 are connected to the same inputs of subregister 3.

The device works as follows.

The device reproduces information recorded on a carrier, the tracks of which are divided into two groups equally, forming two channels. In each of the channels, the middle tracks are occupied by recording — the playback of a sync signal.

The sync pulses from the middle tracks of the groups of channels from the gain unit 1 are fed to the launch of one-shot 4 and 5, the pulse duration of which is shorter than the row-following period at the nominal speed of movement of the carrier. The impulse from the one-shot 4 (5) rear edge sets the trigger 10 (11) to a single position and through block 14 (15) allows the recording of information from the sub-register 2 (3) into

register 6. Through the delay node 12 (13) a sub-register 2 (3) is prepared to receive information.

The output signal of the coincidence circuit 8 appears on the falling edge of the last pulse of the single vibrators 4 and 5. The output signal of the circuit 8 outputs information through resolution block 7, sets the triggers 10 and 11, and registers 6 to receive the information.

The clock pulse from the main output of the one-shot 4 (5) is fed to the input of the element 16 (17), which, by a pulse from the output of the circuit 8, sets the trigger 18 to the position corresponding to the skewing direction of the carrier. The signal from the output of the trigger 18 through the switch 19 (20) commutes the pulses on the trailing and leading edges of the one-vibrator 4 (5) to the corresponding additional inputs of the sub-register 2 (3).

In the presence of a working signal on the second shoulder of the trigger 18, which corresponds to the fact that the bits of the first channel are ahead of the bits

of the second channel, this signal commutes the leading edge of the pulse from the auxiliary output of the 4 (5) oscillator to the first auxiliary input of the subregister 2 (3), and the falling edge of this pulse from the main

one-shot output - to another additional input of sub-register 2 (3). In this case, the subregister 2 (3) records the leading extreme information bits of the first channel along the leading edge of the pulse.

oneBibrator 4 (5), and the lagging bits of this channel - on the falling edge of this pulse.

The information signals from the amplification unit 1 have approximately the same duration as the sync signals at the outputs of the one-shot 4 and 5.

If there is a signal on the first shoulder of the trigger 18, which corresponds to the opposite direction of carrier skewing, it produces a reverse switching of the rear edge of the one-vibrator pulse 4 (5) to the first auxiliary input of the subregister 2 (3), and the leading edge to the other input of the same subregister 2 ( 3).

In order to position the carrier skew trigger 18 in the correct position corresponding to the skew direction of the first line, a zero-line recording-replay containing a sync signal is assumed. Alternatively, a slight bias of the first line should be assumed, in which the position of trigger 18 does not affect the accuracy of reproducing information with it.

The proposed device extends its functionality in terms of preserving the fidelity of the reproduced information in the conditions of instability of the speed of the carrier in the recording-reproducing path.

Claims (1)

Invention Formula Device to compensate for media skew on ed. St. 670966, characterized in that, in order to expand the functionality of the device by maintaining the correctness of the reproduced information when increasing the limits of change of the speed of movement of the information carrier, it is equipped with two AND elements, a skew direction trigger and two switches, while the AND elements, the first inputs of which are connected to the output of the coincidence circuit, and the second with the main outputs of the corresponding channel single vibrators, the outputs are connected via a skew direction trigger with the first second red switching inputs of switches, switched third and fourth inputs of which are connected respectively to the main and additional outputs of the respective single-oscillators, and the first and second outputs respectively to the additional first and second inputs of the respective subregisters. Sources of information taken into account in the examination the USSR 15 1. Copyright certificate № 670966, cl. G 11B 5/43, 1978.