Lutron Electronics SL-4010 - Front Panel Description; Microphone and Display Identification; Control Switches and Indicators; Battery Compartment Location

3. FRONT PANEL DESCRIPTION
3-1 Electric condenser microphone
3-2 Display
3-3 Range upper / lower indicator
3-4 Range switch
3-5 External calibration VR
3-6 Power ON/OFF/Hold switch
" 1 " = Power ON " 0 " = Power OFF
3-7 Battery compartment / Cover
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