Center 323 - Battery Capacity Indicator; External Power Supply Usage; Operating Precautions

Sound Level Meter
10
Remove the battery cover on the back and put in four (1.5V,size
AAA)Batteries, paying attention to the polarity as indicated in the
compartment.
Note:
It is possible to use size AAA rechargeable batteries, but a separate
charger must be provided for such batteries, since the unit is not designed
to recharge batteries.
(2) Battery capacity indicator:
When operating the unit on batteries, periodically check this indicator to
determine the remaining battery capacity.
(3) External power supply:
When the AC/DC adapter is used, insert the plugs of the adapter into the
DC5V connector.
Note: When the AC/DC adapter is connected, the unit will be powered form
the adapter, also when batteries are inserted.(The AC/DC adapter has
priority)
10. OPERATING PRECAUTIONS
(1) Wind blowing across the microphone would bring additional extraneous
noise.
When using the instrument in the presence of wind, it is a must to mount the
windscreen to not pick up undesirable signals.
(2) Calibrate the instrument before operation if the instrument was not in use
for a long time or operated in bad environment.
(3) Do not store or operate the instrument at high temperature and high
humidity environment.
(4) Keep microphone dry and avoid severe vibration.
(5) Please take out the battery and keep the instrument in low humidity
environment when not in use.