SU371855A1 - Device for transmitting an audio signal in the frequency band of a television signal - Google Patents

Description

one

The invention relates to devices for transmitting sound signals, broadcasting and other low-frequency messages in the frequency band of a television signal by a pulse method.

Devices are known for transmitting image and sound signals in one channel by means of an audio information converter into a sequence of modulated sound-carrying pulses located in lowercase quenching intervals.

However, in such devices there is no instantaneous compatibility of black-and-white and color transmissions and the noise immunity of the soundtrack channel is not fully realized.

The proposed device has instant compatibility of black and white and color transmissions and, in addition, has increased noise immunity of image, sound and synchronization signals.

The drawing shows a block diagram of the proposed device.

The device contains a linear and nonlinear image signal processing circuit 1, a line 2 and frame dimming processing circuit 2, an adder 3, a low-frequency paraphase amplifier 4, a dynamic memory circuit 5, a synchronous information reading circuit 6, a rewriter pulse shaper 7, a waiting multivibrator 8, a delay line 9, an anti-coincidence circuit 10, a circuit for the sound-carrying pulses linear processing 11, a synchronization circuit 12, a circuit 13 for generating noise-resistant synchronization signals. The device works as follows.

Scheme 1 of linear and nonlinear image signal processing boosts the higher frequencies of the television signal spectrum (with a well-defined phase response), amplifies the linear predistortion signal, and symmetrically limits the outliers. The nonlinearly processed signal enters the circuit 2 processing line and frame blanking intervals, which counts the horizontal and frame blanking

intervals, passively regenerates the protective packets of the color subcarrier signals and the identification signals. A television signal, variously processed in the active part of the lines and dimming intervals, is fed to the first

adder input 3.

From the outputs of the paraphase low-frequency amplifier 4, antiphase audio signals are fed to the dynamic memory circuits 5, which fix the value of the audio information with a double horizontal frequency.

The synchronous read control circuit 6 connects, in time with the signals from the generator 7, the pulses of the redirection of the end elements of the dynamic memory to the bit circuits of the waiting multivibrators 8.

The duration of the cumulative storage elements of the dynamic memory is proportional to the value of the sound information fixed with a double line frequency, and the rewriting pulses follow the line frequency and allow to store in the dynamic us until the occurrence of the lowering blanking interval only that sound part of the string.

Two-way width-modulated sound-carrying pulses of a predetermined duration, located in lower-case damping intervals, are formed from signals from pending multivibrators using an output delay line 9 at the output of the anti-sweep circuit 10.

For simultaneous non-transmission of a color subcarrier and sound-carrying pulses, as well as to achieve maximum noise immunity of the soundtrack channel, linear sound processing pulses circuit 11 converts the spectrum of sound-carrying pulses ).

The timing circuit 12 generates from the sync mixture of the input television signal the pulse sequences controlling the device. The specified accuracy of the synchronization system of the receiving device is provided by the circuit 13 for generating the noise-resistant synchronization signals, which generate the synchronization signal in the form of a code combination, which is fed to the third input of the adder. At the output of the adder, a combined television signal is formed.

Subject invention

An apparatus for transmitting a sonic sounding signal in a television signal frequency band by latitudinal modulation of a sequence of dual pulses located at dimming intervals of a sync signal, comprising a sound information converter in a sequence of two-sided width-modulated pulses, a sync circuit and a linear and non-linear image signal processing circuit, characterized in that, in order to increase the instantaneous compatibility of the sound signal

and images during the transfer of black-and-white and color images, the output of the linear and non-linear image signal processing circuit is connected to the block of processing line and frame blanking intervals, connected

sequentially with an adder, to the inputs of which signals are fed from the synchronization circuit, and to another input of the adder, the signal from the audio information converter is fed into the sequence of two-sided width-modulated pulses through a two-channel pattern of sound-generating pulses, the outputs of the channels are connected to the anti-coincidence circuit directly and through the delay line, and in each channel a standby multivibrator, bl a dynamic memory controlled by a signal from the read control circuit information, and a pulse shaper.

Combined output

signal