Optimus EDC-1000 Series Instruction Manual page 22

2. OPERATION
2.1. Functionality of main unit's front panel
(1) Conference system configuration buttons:
Mode: Mode selection button.
UP: Setting up a parameter or increase the volume.
Down: Setting down a parameter or decrease the volume.
(2) Power switch.
(3) Output volume LED indicator: LED bar indicates the volume of the output level.
(4) Display Control LCD 20x4.
EDC-1000 Version 2
EDC-1000 SERIES
Conference System
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