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Hardware Installation Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Logic Input And Output

Push To Talk Microphones

The SoundStructure devices may be used with push to talk microphones such
as the Shure MX392.
When the orange (LED in) wire is connected to ground due to the
SoundStructure logic output being turned on, the LED on the microphone will
turn on. The LED is powered from the SoundStructure phantom power
supply on the red and black cables. This means that the LED on the
microphone does not need external power through a pull-up resistor on the
orange (LED in) wire. The shield of the cable provides a ground for the entire
audio and logic circuit even though there is a separate green wire for Logic
Ground. This means that the green wire does not need to be connected to
SoundStructure device. One could connect the green wire to the shield at the
mic side and then only need to run a 4-conductor cable plus shield to the
SoundStructure device, or one could run the microphone's logic ground to the
ground on the logic connector.
No current-limiting resistors are needed between the microphone and the
SoundStructure device as the current on the Orange (LED IN) wire when the
LED is on is on the order of microamps.

Remote Control

Analog Input

Pin 2 : Logic Output 1
Pin 25 : Ground
Pin 14 : Logic Input 1 White
Orange
Green
Red
Black
Shield