Instruction manual

11
Controls and Functions
Power switch
This sliding switch serves to turn the unit on and off.
Contrast control
Serves to adjust the display contrast. Use the supplied miniature screwdriver for the
adjustment.
Backlight key
Pressing this key activates the display backlight. After about one minute, the backlight
turns itself off automatically.
EXT DC IN connector
The optional AC adapter NC-94A can be connected here for powering the unit from an
AC outlet.
Trigger input connector
Serves to control of the measurement by trigger function.
DC output connector
A DC signal corresponding to the sound pressure level is available at this output. The
I/O menu screen can be used to select the main channel or sub channel for output
(serves for maintenance).
AC output connector
A frequency-weighted AC signal corresponding to the sound pressure is available at
this output. This can be supplied to a level recorder such as the optional LR-04 or
LR-06 or to a data recorder. By using the optional splitter adapter, a separate signal
for the main channel and sub channel can be obtained.
Calibration control
Serves to carry out calibration, using the supplied miniature screwdriver.