17
5. CALIBRATION PROCEDURES 
①  Make the following switch 
settings:  
Frequency weighting: A-weighting 
Time weighting: FAST 
Level range: 50 ~100dB 
②Insert the microphone housing carefully 
into the 1/2 inch insertion hole of the 
calibrator(94dB @ 1kHZ).   
③ Turn on the switch of calibrator and 
adjust the CALL potentiometer of the 
unit 94.0dB is displayed.   
NOTE: All products are well calibrated 
before shipment. Recommended 
recalibration cycle: 1 year.   
Acoustic Calibrator
REC
FAST
A/C
DC  9V
OUTPUT
CAL
 
6. MEASUREMENT PREPARATION 
① Remove the battery cover on the back