The video amplifier is used to extend the range of Gira door communication systems to include video function. It increases the volume of the incoming video signal to the maximum permissible bus volume and makes this available at the output, thereby compensating for the line attenuation from the source of the video signal to the input of the video amplifier.
With a video amplifier, the cable length between the door and home station can be extended by 100 m to a maximum of 200 m.