SU907831A1 - Device for correcting for phases of stereophonic signals - Google Patents

Description

(5) DEVICE OF CORRECTION OF STEREO-PHONES PHASES

SIGNY SE

one

The invention relates to communications and can be used in long-distance high-frequency audio broadcasting channels.

A device for correcting the phase of stereo signals is known, each of the stereopair channels having serially connected primary group converters and bpoc individual transducers, the second outputs of the primary group converters connected to the inputs of the corresponding first filters, second filters and two transmission units, as well as a crystal oscillator, the output of the unit of individual converters of the first channel is connected to the first run of the first transmission unit, the second input of which is connected to the first output of the second filter of the first channel 1.

However, the known device introduces relatively large distortions.

The aim of the invention is to reduce the distortion of stereo signals.

To achieve this goal, a phase detector, a narrowband phase shifter, a wideband phase shifter and an adder are added to each channel of the stereo pair, the first inputs of which are connected to the outputs of the respective first filters, the second inputs of the adders are connected to the outputs of the crystal oscillator, and the outputs of the adders are connected to the inputs of the second filters, with the output of the indi vidual transducer block of the second channel connected to the first input of the wideband phase shifter, the second input of which connected to the first input of the phase shifter and narrowband

20 output of the phase detector, the first input of which is connected to the second output of the second filter of the first channel, and the second input phase detector

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connected to the first output of the narrowband phase shifter, the second input of which is connected to the output of the second filter of the second channel, while the second output of the narrowband phase shifter is connected to the first input of the second block in front, the second input of which is connected to the output of the wideband phase shifter.

The drawing shows a structural electrical circuit of the proposed device.

The phase correction device of stereo signals contains in each channel of a stereo pair a unit 1 for converting primary groups, a unit 2 for individual converters, a block 3 for transmission, a first filter, an adder 5, a second filter b, and also a crystal oscillator 7, a narrowband phase shifter 8, a phase detector 9 and a wideband phase shifter 10.

The device works as follows.

The first and second channels of the stereo pair come with a group signal, which includes, among other information, a broadcast signal and a control signal with a frequency of kHz, which is in the frequency spectrum of the broadcast channel.

In block 2 of the first channel, the broadcast signal of the first channel is separated from the spectrum of the primary group and is fed to the first input of block 3 of the same channel. The broadcast signal of the second channel of the stereo pair, separated from the spectrum of the primary group by the block 2 of the second channel, is fed through the wideband phase shifter 10 to the second input of the block 3 of the same channel. The passage of the broadcast signal of the second channel through the wideband phase channel: the gate 10 is necessary in order to adjust the phase of the broadcast signal of the stereo pair. In both channels of the stereo pair, the first filter separates the voltage of the control frequency 8, kHz from the spectrum of the primary group. Next, the voltage of this frequency is applied to the first input of the adder 5 to the second input of the adder 5, the voltage of 11.86 kHz is supplied from the output of the quartz oscillator 7. Thus, at the output of the adder 5, a voltage of 96 kHz is obtained, which is phased with the received broadcast signal and can be used

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further as the recovered carrier frequency of the second channel of the stereo. Similarly, the voltage of the recovered carrier frequency of the first channel is obtained. By the second filter 6 this restored frequency is separated and fed in the first channel to the first input of the phase detector 9 and in the second channel - to the narrowband phase shifter Vis of its output - to the second input of the phase detector 9If between the stereo pair channels and, consequently, between the recovered voltages the carrier frequencies 9b kg of both channels of the stereo pair arriving at both inputs of the phase detector 9, there is a phase difference, then an output adjustment signal is generated at the output of the phase detector 9, which controls the narrowband phase shifter 8. It regulates liruet phase voltage of the carrier frequency of the second channel as long as there is a discrepancy between the two channels fazmezhdu carrier frequencies. The adjustment signal produced by the phase detector 9 also controls the operation of the wideband phase shifter 10. As long as there is a control signal at the output of the phase detector 9, the wideband phase shifter 10 is aligned (the phase of the broadcast signal of the second channel is output. From the output of the narrowband phase shifter 8, the voltage is restored The carrier frequency 96 kHz of the second channel of the stereo pair, phased with the voltage of the recovered carrier frequency 9b kHz of the first channel, arrives at the first input of block 3 of the second channel.

The proposed device provides a stereo effect with minimal technical and economic costs.

Claims (1)

Invention Formula A phase correction device for stereo signals containing in each channel of a stereo pair serially connected primary group conversion unit and individual converter unit, the second outputs of the primary group conversion units connected to the inputs of the corresponding first filters, second filters and two transmission units, as well as a crystal oscillator the output of the unit of individual transducers of the first channel is connected to the first input of the first transmission unit, the second input of which is connected to the first output of the second filter of the first channel, characterized in that, in order to reduce the distortion of stereo signals, a phase detector, narrowband phase shifter, wideband phase shifter and each are entered channel stereo pair adder, the first inputs of which are connected to the outputs of the respective first filters, the second inputs of the adders are connected to the outputs of the crystal oscillator, and the output rows of adders are connected to corresponding inputs of the second filters, wherein the individual transducers of the second channel unit output is connected to the first input shirokopolonogo phase shifter, a second input coupled to a first input of the narrowband ezovraschatel and output of the phase detector; The first input, which is connected to the second output of the second filter of the first channel, and the second input of the phase detector is connected to the output of the narrowband phase shifter, the second input of which is connected to the output of the second filter of the second channel, while the second output of the narrowband phase shifter is connected to the first input of the second transmission unit, the second input of which is connected to the output of the wideband phase-reflector. Sources of information taken into account in the examination t. Hoso Gijutsu. Automatic phase correction device in stereo broadcasting, 1963tT.l6, No. 2, p. 90-95, 115 (prototype).  6 I- Ei i it k