SU743224A1 - Apparatus for transmitting and receiving facsimile discrete information - Google Patents

Description

one

The invention relates to communication and can be used to transmit and receive discrete information via facsimile communications canal.

A device for transmitting and receiving facsimile discrete information is known, comprising, on the transmitter side, an analyzing unit, the output of which is connected to the input of the first amplifier, a magnetic drum connected to the first and second recording units and the first and second reading units, the first amplitude modulator, the input of which is connected to the output of the second reading unit, and the output to the input of the second amplifier, and on the receiving side the first demodulator connected to the input of the receiver of discrete information, the third amplifier whose output th through second demodulator connected to the input unit 1 synthesis.

However, this device does not allow the transmission of discrete information via a facsimile communication channel.

The aim of the invention is to seal the communication channel by transmitting discrete information between pulses of the main facsimile signal.

To do this, a device for transmitting and receiving facsimile discrete information, containing on the transmitting side an analyzing unit,

5 whose output is connected to the input of the first amplifier, a magnetic drum connected to the first and second recording blocks and to the first and second reading blocks, the first amplitude

About the modulator whose input is connected to the output of the second reading unit, and the output to the input of the second amplifier, and on the receiving side the first demodulator connected to the input of the receiver of discrete information, the third amplifier whose output through the second demodulator to the input of the synthesizing unit, on the transmitting side, the source of the reference

20 voltage, a generator of a linearly varying voltage, the output of each of which is connected respectively to the first and second inputs of the inputted zero-body, the first output of which is connected to the input of the recording unit, and the first input of the generator of a linearly varying voltage ; null-organ, with the output of the first amplifier pod30 keys to the input of the second recording unit

and to the second input of the generator of linearly varying voltage through the input inverter, while the output of the first reading unit is connected to the input of the inputted first one-oscillator and the input of the input delayed unit, the output of which is connected to the first input of the inputted first key through the input second one-oscillator and the output of the first one-oscillator connected to the first input of the entered first adder via the entered second amplitude modulator, the second input of the first adder is connected to the output of the input discrete source This information through a serially connected input of the third amplitude modulator and the first key, while the output of the first adder is connected to the first input of the input of the second adder via the entered fourth amplifier, and the second input of the second adder is connected to the second, the third keys, the signal amplitude detection unit and the third one-shot, the first and second outputs of which are respectively connected to the first inputs of the second and third keys, the output of each of which They are connected respectively to the input of the third amplifier and to the input of the first demodulator, while the volt and second inputs of the second and third switches are interconnected and connected to the input of the third one-oscillator through the signal amplitude detection unit.

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

A device for transmitting and receiving facsimile discrete information contains on the transmitting side an analyzing unit 1, a first amplifier 2, a magnetic drum 3, nepaHff and a second writing unit 4, 5, respectively, the first and second reading units b, 7, respectively, the first amplitude module torus 8, the second amplifier 9f and on the receiving side the first demodulator 10, the receiver 11 of discrete information, the third amplifier 12, the second demodulator 13, the synthesizing unit 14, the device also contains on the transmitting side the source 15 of the reference voltage, : rater 16 linearly varying voltage, zero-body 17, inverter 18, first one-shot 19, delay block 20, first key 21, second one-shot 22, first adder 23 second amplitude modulator 24, discrete information source 25, third amplitude link torus 26, the second adder 27, the fourth amplifier 28, and on the receiving side - the second key 29, the third key 30, block

31 distinguish the amplitude of the signal, the third one-shot 32.

The device works as follows.

A sequence of pauses and impulses that correspond to the level

black on the original, from the output of the transducer amplifier 2 is fed simultaneously to the input of the inverter 18 and through the second recording unit 5 to the magnetic drum 3, in which it is recorded with a delay tj. The inverted in the interval 18 sequence is fed to the second input of the generator 16, the output of which is formed

 linearly varying voltage. a zero-body 17 arriving at the second input 17. A reference voltage is applied to the first input 17 of the source 17, the level of which determines the period of the operation of the zero-body 17.

0 Due to the feedback between the null-organ 17 and the generator 16, a sequence of pulses of a linearly varying voltage is formed at the output of the latter. At the first output

5 of the zero-body 17 a sequence of short pulses is produced, arising at the moments of equality of the reference and linearly varying stresses. This sequence through

0, the first recording unit 4 is also recorded on the magnetic drum 3.

When the first and second read blocks B and 7 are read, pulse sequences are formed at their outputs, shifted by the delay time tj. If the pause is greater than t, then an integer number of short pulses is formed in it, if less, then there will be no recorded short pulses. Short pulses are intended for

 control the alternation of the transmission of pulses recorded on the magnetic drum 3 with a delay of t and discrete information packets. When the first reading unit 6 reads, a short pulse triggers the first one-shot 19, which produces a short, increased amplitude pulse. These pulses are applied to the input of the second amplitude modulator 24,

0 after which, modulated, they arrive at the first input of the first adder 23. Simultaneously, from the first reading block b, the pulse delayed by t (transient time

e) a delay block 2-0, starts the second odiovibrator 22 with a constant time t On ry produces pulses of duration tg. These pulses open the first key 21, and the signals from the source of discrete information 25 pass through the third amplitude modulator 26 to the second input of the first adder 23.

The output of the first adder 23

5, a sequence is formed, consisting of short pulses of increased amplitude and signals of discrete information, which through the fourth amplifier 28 is fed to the first input of the second adder 27. A sequence of pulses corresponding to the black level on the original, is output to the first amplitude the modulator 8, from the output of which the amplitude-modulated signal, pre-amplified in the second amplifier 9, is fed to the second input of the second adder 27, From the output of the second adder 27 line (not shown) receives a sequence of signals consisting of discrete parcels of information and pulses black image levels.

In the receiving part, this sequence of signals is fed to the input of block 31, which, when triggered, triggers the third one-shot 32 with a constant time tg. The second key 29 is in the initial state open, and the third key 30 is closed. The third one-shot 32, triggered, closes the second key 29 and opens the third key 30. Sending discrete information that follow higher amplitude pulses go to the first demodulator 10 and further to the receiver 11. If a high amplitude pulse does not follow through t, This opens the second key 29 (the third key 30 closes), and the black level pulses, after amplification and demodulation in the third amplifier 12 and the second demodulator 13, enter the synthesizing unit 14, where the image is played.

The proposed device allows to obtain a significant gain in the efficiency of the use of the communication line due to the transmission of discrete information in the intervals between the pulse {and the main facsimile signal.

Claims (1)

1. Japanese Patent 4925765, cl. 97 (3) A-411, published. 1974 (prototype)