Extech Instruments 407790 User Manual page 10

Instantaneous sound pressure level measurement (L
To perform a measurement, carry out the following steps.
1. Set the power switch to ON and wait until the measurement screen appears.
ID No: 00001358
Self-Testing...
2. Press the SLM/ 1/1/ 1/3 button to select the desired SLM, 1/1 or 1/3 octave band
sound pressure level measurement screen.
FAST
L
A
dB
100
90
80
70
60
50
40
30
Hz 31.5
[ 1 / 1 OCT ] 01 / 07 / 27 14:26:39
3. Use the FREQ WGHT button to select the desired L
setting.
4. Use the TIME CONST button to select the desired FAST or SLOW time constant
setting. Normally, the "FAST" setting should be used.
5. Use the LEVEL
and "UNDER" indications do not appear. In SLM mode, the dynamic range is
30~130dB so the
SOUND LEVEL METER
1/1 & 1/3 Octave Band
Real-Time Analyzer
W
125 500 2k
button to select the range. Choose a setting in which the "OVER"
LEVEL
Ver: 0.10
FAST
30
[ SLM
FAST
75.2 dB
dB
100
90
80
70
60
50
40
30
8k L W
Hz 31.5
[ 1 / 3 OCT ] 01 / 07/ 27 14:26:39
button is not used.
10
, L , L )
A C P
L
A
80
] 01 / 07 / 27 14:26:39
L
A W
125 500 2k
, L or L frequency weighting
A C P
Model 407790 Ver. 1.1 7/02L
dB
130
75.2 dB
8k L W