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Automatic Gain Control The automatic gain control (AGC) of the audio signal is designed to make used to bring the volume of the audio signal volume to a constant level. You can configure the AGC mechanism should be set only with the use of only when you use sound cards of Olha line series: Olha-9P, Olha-10LP, Olha-12U, Olha-14.

It is recommended to use AGC when input audio signal power is unsteady  You can use the AGC mechanism in conditions of uneven power of the incoming audio signal or when the power of the sound audio signals , coming from different sources and forming the joint aggregate audio signal , differs significantly. The AGC mechanism levels out the power levels of audio signal components from different audio sources.

Axxon PSIM™ software has an AGC adjust option. AGC PSIM provides a possibility to configure the AGC mechanism according to the operating conditions. The AGC mechanism has two adjustable parameters: a target the power level, to which the AGC brings different both more and less powerful audio signals, and the adjustment time of bringing to bring the audio signal to the target specified power level. The second parameter has certain restrictions: the less time it takes of the AGC mechanism has the following limitations: the shorter the time to bring the audio signal to a certain the required power level, the lower the quality of AGC operation , which may result in greater and the greater the power level jumps fluctuations in the processed signal. However, a longer adjustment time At the same time, increasing the time of bringing the audio signal to the required power level lengthens the areas where the power of the processed audio signal builds up and decreases. SoThus, processing may can bring sizable distortions into the audio signal. Hence, AGC settings depend substantially Due to these circumstances, the values of AGC mechanism parameters depend to a great extent on the conditions of audio signal formation, and when these conditions have been changed, new AGC settings should be set.you must configure the AGC again if they change significantly.

The AGC mechanism is applied to each audio signal coming AGC is independently applied to any audio signal from any microphone of the video surveillance and audio monitoring system.

By default, the AGC mechanism is disabled. The AGC option is enabled You must configure the AGC for each microphone independently.

To set up configure the AGC follow , do the stepsfollowing:

1. Go to the settings panel of the Microphone system object.
   Image ModifiedSet
2. the Enable checkmark in In the AGC group (1), set the Enable checkbox.
   As a result, sliders in the AGC group Dinamic Dynamic range and Time constant are activated (2,3) sliders become active.
3. Set Move the Dynamic range slider to the position , corresponding to the desired required level of video signal’s output power of the video signal. The current power value, measured value of the output power level in decibels , is shown in the field on the displayed to the right of the slider (2).
4. Set Move the Time constant slider to the position that corresponds corresponding to the time of bringing the signal to the defined required power level. The value of the time constant in seconds , set by the slider, is displayed on to the right of it (3)the slider.
5. Click the Apply button to save all the changes (4).
6. It is recommended to check AGC correctness after the settings were madeAfter you set the parameters of the AGC mechanism, we recommend checking the correctness of the settings. To do sothis, use one of the audio playback devices of the tools provided in Axxon PSIM ™ software, for example, the Audio player object. Beforehand, you must configure the Audio player should be preset for to play audio signals playback.
   1. If the power of the audio signal
   power is too high
   1. is higher than the required power, move the Dynamic range slider
   some points
   1. a few divisions to the left. If the power of the audio signal
   power is too low
   1. is lower than the required power, move the Dynamic range slider
   some points
   1. a few divisions to the right.
   2. If
   increasing and decreasing of audio signal power is perceptible
   1. you notice a rising or falling power level in the audio signal, move the Time constant slider
   some points
   1. a few divisions to the left.
   If significant jumps in audio signal power are perceptible
   1. In case there is a significant power level difference for different periods of the audio signal being played back, move the Time constant slider
   some points
   1. a few divisions to the right.
7. When If necessary, repeat 7steps 6a-10 steps6b. If AGCis the AGC mechanism is set up correctly, finish AGC complete the setting up procedure.

AGC setting up is completedSetting up the automatic gain control is complete.