GS1U-057 AUTOMATIC SWITCH
This is a mains powered 1RU subrack. It is designed to automatically switch in an external audio device (e.g. optimod processor). It is a 2 part system, 1 part being a 19kHz generator and fixed mixer and the 2nd part being a 19kHz detector, filter & switch.
A stereo audio input has the 19kHz tone mixed with it and sent
to an output.
This output is fed to an external mixer.
The output of the external mixer is fed back into the GS1U-057.
When the external mixer mixes in its input from the GS1U-057 to its output the
GS1U-057 will detect the 19kHz tone.
If no 19kHz tone is detected then the output of the GS1U-057 is fed straight
from the input from the external mixer.
If 19kHz tone is detected then an external stereo audio device is switched into
circuit.
A 19kHz notch filter is provided to remove the 19kHz tone from the units audio
output.