Galaxy Audio CHECK MATE CM-160 - Manual (Page 11)

MAX / MIN hold button
Select the proper level range before using MAX/MIN to ensure
that the reading value will not exceed the measurement range.
Press button to enter the maximum and minimum recording
mode. Press once to select MAX value. Press again to select MIN
value, and press again to select current value with “ MAX/MIN “
annunciator blinking. Press and hold it down for 2 seconds to
exit the MAX/MIN mode.
Note: If the sound level range or A-C weighting is changed, the MAX/
MIN mode will clear.
Record Data logger button
When the button is pressed, the meter will start recording and
the “REC” annunciator is displayed. Press again to stop recording.
Frequency Weighting select button
A: A - Weighting filters out low frequencies to approximate the response
of the human ear at lower SPL's.
C: C - Weighting filters less low frequencies to approximate the response
of the human ear at higher SPL's. (a flatter response.)
Time weighting select button
FAST: for normal measurements
SLOW: for checking the average level of fluctuating noise.
Level range control button
Each time you press button, the level range will rotate between
“Lo” level, "Med” level, “Hi” level and “Auto” level.
Microphone
1/2 inch Electret Condenser microphone
CAL potentiometer
Calibration control for level calibration adjustment.
USB Interface:
The USB signal output is a 9600 bps USB interface.
TX
RX
GND