Galaxy Audio CHECK MATE CM-200 - Manual (Page 9)

(3)
If 114dB is selected on the calibrator, choose a range
with an upper limit of 120dB. The instrument may be
set to FAST or SLOW response and C or A weighting.
(4)
(5) Read the level on the instrument under test and adjust
the sensitivity control for the correct indication of the
sound level calibrator level selected in step 3.
(6) When the calibrator is not in use, please switch OFF
the power to save the battery.
CAUTION!
If 94dB is selected on the calibrator, then choose a
level range on the instrument under test to a range
having 100dB as it’s upper limit.
Insert the microphone of the of the instrument being
calibrated all the way into the cavity of the calibrator.
Hold the two together so that the instrument remains
straight into the calibrator during the test.
Ambient sources of noise or vibration can cause a
false calibration indication. This can be especially
significant at the lower 94dB level.
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