Polycom manual SHURE MX392 BASICS

SHURE® MX392 BASICS

The Shure MX392 is a surface-mount, electret microphone that includes a programmable membrane on/off switch that can be controlled externally via logic input / output terminals. This application note explores how to connect the MX392 to a Vortex device (EF2280, EF2241, EF2201, EF2210, or EF2211) as well as how to program the Vortex device and MX392 to achieve the desired control over the membrane switch.

The MX392 includes three extra conductors as part of the microphone cable:

•LOGIC GND (Green): Connects to the logic ground of the Vortex Device. This can be either Pin 25 of the Logic Input port or Pins 21-25 of the Logic Output port.

•SWITCH OUT (White): Provides a TTL logic low when the membrane switch is pressed. This signal is available at all times for all switch settings. The SWITCH OUT function provides a momentary closure when S1 is OFF and a latching closure when S1 is ON. This conductor will go to one of the Logic Input Pins of the Vortex Device (Pins 1-24).

•LED IN (Orange): This terminal draws 5 V DC. This function can be modified so that the Vortex Device controls the action of the LED by flipping S3 to the ON position. If this terminal is shorted to LOGIC GND, the LED turns on.

The MX392 includes a set of 4 DIP switches that are located on the printed circuit board of the microphone. These DIP switches change the functionality of the membrane switch. For reference, here is a list of all possible functions of the switch:

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