Download Larson Davis Model 814 Sound Level Meter

Backlight
On/Off
Turns backlight on/off.
LCD Contrast
0 - 99%
Adjusts the viewing angle of the LCD
display. This is done by pressing either
the up or down arrow key. The u
key increases the contrast percentage,
darkens the display and makes it visible from a higher angle (when viewing
from the bottom of the instrument).
The d key decreases the contrast
percentage, lightens the display and
makes it more visible from a lower
angle.
External Power
AC Pwr
Battery
Allows the user to select the source of
power consumption, either AC or battery.
- Indicates that the external
power source is not a battery. In this
mode, if the external voltage is less
than the internal battery voltage, then
the internal batteries will supply
power for the instrument.
AC Pwr
Battery - Indicates that the external
power source is a battery (which
should not be allowed to deep-discharge).
Extra Notes on Power Conservation
If you are using an external power supply, rather than
a battery, the v key will display the constant voltage
coming from the power supply. The System 814 can
operate for approximately 40 four hours when it is
running from new alkaline batteries. The instrument
can be set to conserve the internal batteries for memory retention only if it is to be powered by an external
power source by setting Ext Power to [Battery]. If the
external supply ever drops below the voltage set by
the Cut Off Volts setting, or reverts to internal battery,
the unit stops and turns off. This cut-off voltage is usu2/27/98
Reference
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