14
8. CALIBRATION PROCEDURE
Most national standards recommend that you calibrate your sound level meter before
each set of measurements and check the calibration after each set.
The procedure to check/adjust the displayed sound level in response to acoustic
calibrator types TES-1356 or equivalent is as follows:
1. Turn off the sound calibrator.
2. Press the
button to turn on the instrument.
3. Use the “
”
buttons to select the 60 to 120dB
reference sound level range.
4. Use the “
A / C
” button to select “A” frequency weighting.
5. Use the “
SLOW
IMPUSE
FAST
”
button to select “FAST” time weighting.
6. Insert the microphone very carefully and slowly all the way
into the sound calibrator coupling orifice.
7. Switch on the 1000Hz sound calibrator in its nominal 94 dB
level setting.
8. Adjust the CAL potentiometer of the instrument, until the
display reading for diffuse field is the same as the certified
pressure level of the calibrator, or is 0.1 dB higher than this
pressure level for free-field. This applies to calibrators type
TES-1356.
9. Set the power switch of the sound calibrator to OFF.
10. Remove the microphone very carefully and slowly from the
coupler.
SOUND-LEVEL
CALIBRATOR
114dB
1KHz
OFF
94dB
INTEG
DATE
TIME
TIME
ERASE
Leq SEL SPL
RECORD
MAX
A/C
