4) Slide the " A/C weighting selector " ( 3-7, Fig. 1 )
to " A weighting " position.
5) Carefully adjust the " Calibration VR " ( 3-5, Fig. 1 )
with " - " screw driver (include accessory ), until the
display read within " 94.0 ± 0.2 " dB.
8-2 Calibrated via internal 94 dB generator The
sound level meter is built in the internal standard 94 dB/1
KHz square wave generator for the purpose to calibrate
come certain amplifier circuit ( not the complete meter
system ). Please according the following procedures to
calibrate the instrument before making operation, if the
instrument not in use for a long time. The calibration
method are similar as above 8-1, but not connect the
external sound calibrator ( SC-941, SC-942... ), the
other should slide " Power off/On/Internal calibration
selector " ( 3-10 , Fig. 1 ) to the " CAL. " position "
Carefully adjust the " Calibration VR " ( 3-5, Fig. 1 )
with " - " screw driver ( included accessory ), until the
display read within " 94.0 0.2 " dB.
Note :
If intend to make calibration
accurately of whole meter, it is
recommended to use the calibrating
procedures of above 8-1 " Calibrated via
external SOUND CALIBRATOR "
9
