Measurements; Sound Level Measurements - Extech Instruments 407790A User Manual

4. Measurements

All processing functions provided by the meter (Leq, SEL, Lmax, Lmin, Ln) are carried out
simultaneously. For example, when equivalent continuous sound level measurement is selected,
the sound exposure level and percentile level are also determined.

4.1 Sound Level Measurements

1. Press the power button to power on the meter. After the power-on screen displays the SLM
measurement screen will appear.
The measurement parameter settings that were active before the meter was turned off will be
saved.
2. Use the FREQ WEIGHT TIME button to select the Main Channel frequency weighting
characteristic. For normal sound level measurements, select the "A" setting.
3. Use the FREQ WEIGHT TIME button to select the Main Channel time weighting characteristic.
For normal sound level measurements, select the "F" (Fast) setting.
4. Use the  LEVEL  buttons to set the dB level range. Choose a setting in the middle of the
display range of the main channel bar graph indicator.
If the "OV" or "UN" indicators appear, change the level range setting.
5. The Main channel and Sub channel level indicators display the currently measured sound
pressure levels. The reading is updated once every second.
6. The PAUSE/CONT button can be used to stop and resume the updating of the level indication.
In sound level meter mode, the bar graph indication will stop during pause.
In the pause condition, a pause symbol ( ) appears on the display.
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