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Operation before measurement
Table 2 Definition of symbol
4.1 Check list
① Check whether the microphone has been installed correctly.
② Check whether battery has been put in.
③ If necessary, calibrate it with a sound calibrator.
④ The meter should be tested by relative department regularly (such as one year) to
ensure its accuracy.
4.2 Use of windscreen
If windy, you may use a windscreen to reduce influence of wind noise. There are differ-
ent types of windscreens to choose. A
φ
35×60 size windscreen can reduce noise about
10dB-15dB
,
See Appendix D, the influence of free-field responses for a meter with a
windscreen when there is no wind.
4.3 External power supply
The Sound Level Meter can be connected with external power through the
φ 1.1 external
power socket at the lower right of the instrument. At this time, the inner battery will be
cut-off automatically. The voltage range of the external power supply is 4.5V~9V. The
shell of plug is the cathode and the core of plug is the anode. When the Sound Level
Meter is used continuously for a long time, it is recommended to use an external power
supply.
Symbol Definition
Battery level display
Microphone setup: diffusion field type
Integrating measurement and statistical
analysis are in progress
Integrating measurement and statistical
analysis are paused
logging the varying waves of SPL with time
Recording
The measured signal surpasses the upper limit
of measurement range
The measured signal under the lower limit of
measurement range
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