Sennheiser Evolution EW100 Instruction Manual page 21

Battery status indication
The red LED provides information on the (remaining) battery capacity:
LED lit up:
The transmitter is switched on and the battery capacity is sufficient.
LED flashing:
The battery is going flat! You should immediately replace the battery!
Changing the microphone module
First remove the battery and leave the radiomicrophone open.
Unscrew the sound inlet basket.
Loosen the screw and put it aside.
Remove the microphone module, as shown. Do not touch the contacts!
Insert the new module, secure the capsule by tightening the screw,
put on the suitable sound inlet basket and coloured identification ring
and screw it tight.
Insert the battery, close the radiomicrophone and put it into operation.
Note:
Microphone module, sound inlet basket and foam insert form an
acoustic unit and must therefore always be exchanged all together.
Each microphone module comes with a colour-coded identification
ring to distinguish different microphone modules from each other
(green = MD 835, blue = MD 845, red = ME 865).
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