SU1373334A3 - Device for checking level of output signal - Google Patents

Abstract

This invention relates to multi-channel signal transmission paths. Increased reliability. The device contains a communication line (LS) 1, two channels 2 and 2, voltage dividers 3.8, adjustable y-4, intermediate y-5, output y-6, y-9, detector 10, el - compared with the reference voltage II, indicator 16. The goal is achieved by the introduction of two directional couplers 7.18, a comparator (K) 12, a delay of 13, an El And 14, an inverter 15, keys WITH with with with with with

Description

(k) 17.19, mixing source 20. Both channels 2, 2 through K 17 and directional couplers 7.18 m. connected to LAN 1. One of the channels is connected, which is in good condition. The health state is determined by K 12. If both channels are in good condition, the channel is selected by connecting K 19 to AND 1A. If the voltage at the output of the comparison unit 11 is outside the tolerance level and the output level is 3333A

voltage, then K I2 generates a signal, to-ry through the delay delay 13, and 14 and the inverter 15 disconnects K 17 and the indicator 16 generates a fault signal. At the same time, the elect I 14 of another channel begins to produce a voltage connecting via K 17 and the directional coupler 18 to the high voltage of this channel to LS 1. T. arr. ensures reliable operation of the device. 1 il.

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The invention relates to multichannel signal transmission paths, for example, to collective television reception systems, at the nodal points of which various signal sources, such as power amplifiers, can be connected.

The aim of the invention is to increase reliability.

The drawing shows a structural electrical circuit of the device for controlling the output signal level.

The output level control device contains a communication line 1, the first and second channels 2 and 2, each of the channels contains serially connected input voltage divider 3, adjustable 4, intermediate 5 and output 6 amplifiers, first directional coupler 7, ADDITIONAL divider 8 for example amplifier, amplifier 9, detector 10, reference element 11, reference voltage, comparator 12, delay element 13, element 14, inverter 15, indicator 16, key I7, second directional coupler 18, additional key 19, and bias source 20.

The output level control device operates as follows.

Both channels 2 and 2 through the keys 17 and the directional couplers 7.18 can be connected to the communication line 1, and always one of the channels is connected, which is operational. The health state is determined by comparator 12. If both channels are healthy.

Then the channel is selected for connection by connecting the additional key 19 to the corresponding AND 14 element.

5 The input voltage divider 3 matches the nominal level of the input signal with the input level of adjustable amplifier 4. The signal is then amplified in intermediate 5 and output tO n 6 amplifiers and through the first directional coupler 7 is fed as an automatic gain control loop (AGC) from the additional divider 8 for example, amplifier 9, detector 10 and

a comparison element 11 with a reference voltage, and through a switch 17 to a second directional coupler 18 for supplying voltage to the communication line 1.

0 Due to the operation of the AGC loop, the voltage at the outputs of the first directional coupler 7 is maintained within specified limits when the device is operating properly. This normal state is fixed by the comparator 12, at the output of which a health signal is produced, arriving through the delay element 13 switched on for the purpose of delaying the connection to the line until the end

 transient, the element And 14 and the inverter 15 to the key 17 and turns it on, and the indicator 16 fixes the normal operation.

Through the switch 17, the high-frequency voltage enters the second directional coupler 18 and through it into the communication line 1. In this case, the voltage at the output of the element And 14 one kana

la through the element And 14 of another channel opens the key 17 of this channel.

If the voltage at the output of the comparison element 1I lies outside the tolerance field for the output voltage level (outside the control zone), the comparator 12 generates a signal (level) which, through delay element 13, element 14 and inverter 15, turns off (opening) the switch 17 and the indicator 16 generates a fault signal, however, at the same time, the And channel 14 element of the other channel starts to generate a voltage (level) connecting via the switch I7 and the second directional coupler 18 the high-frequency voltage of this channel to the link 1. This ensures reliable operation of the device.

When the initial power is turned on, it is possible to turn on one of them when both channels are healthy, so when the additional key 19 and source 20 are biased, the potential disconnects the second channel to the other input of the second channel element 14 when the additional key 19 is closed. channel, and the input of the inverter 15 of the first channel receives the potential that provides the connection of the first channel. This state is maintained as long as the high-frequency voltage at the output of the first channel 2 is within the tolerance field. If this condition is not met, the second channel 2 is automatically activated.

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Claims (1)

An invention of an output level control device comprising a communication line and first and second channels, each of which is configured as a series-connected input voltage divider, adjustable, intermediate and output amplifiers, as well as series-connected additional voltage divider, amplifier, a detector and a reference element with a reference voltage, the output of which is connected to the control input of an adjustable amplifier, characterized in that, in order to increase reliability, in each channel connected to the output of the output amplifier are connected in series the first directional coupler, the key and the second directional coupler, the other output of the first directional coupler is connected to the additional voltage divider, between the output of the reference element and the reference voltage and the comparator, the delay element, the element And and the inverter, an indicator is connected to the output of the inverter, and in series with the output of the element And the first channel are connected in series the additional ones A key and an offset source, while the output of the AND element of one channel is connected to another input of the AND element of another channel, and the outputs of the second directional channel repeaters are connected to the communication line.