
6.5.3.1 Adjust the amplitude of AC output
Move the cursor to “AC”, press or key to set up the amplitude of AC output.
There’re three gears can be set and each gear differs 10 times. “31mV/Pa” means when
microphone gets 1 Pa sound pressure, the pins of AC output will output about 31mV AC
signal. When the AC output is set to 316 mV/Pa or 3162mV/Pa, the amplitude of the AC
output will increase on the same pressure, but when the sound pressure effects on the
microphone is too high, AC output may distort.
Behind “W”, “Z” means do not take frequency weighting, “A” means the AC output signal
do A frequency weighting, “C” means the AC output signal do C frequency weighting.
Move the cursor to “W”, the frequency can be changed.
The instrument can be auto-off when there’s no operation in a period of time (except
“On” Key), it is possible to cancel this function. When the second row shows “10s” behind
“Auto-off”, means if more than 10s with no operation, the instrument will be auto-off. If
it shows “invalid”, it means the auto-off function is invalid. Move the cursor to
“Auto-off”, press or key can change “Auto-off” between “invalid” and “10s”, “20
s”, “30 s”, “40 s”, “50 s”, “60 s”, “70s”, “80s”, “90s”.
The value of “Limit” is limit value on the third row. When the instrument is under the
measuring interface, the measured instantaneous sound pressure level is greater than
the limit value, “Lamp” light at the bottom of the instrument will be lighted up for at
least one second. Move the cursor to “Limit” and press or key to adjust the
threshold value between 20-140 dB.
If the user matched serial port, the RS232 output port at the bottom of the instrument
can be connected with PC for data transmission, move cursor to “Baud rate of” and
press or key can change “Baud rate” between “9600”, “19200”, “57600”.
Note: After changing the baud rate, please press “ ” key to save the changed baud
rate, otherwise the change will be invalid.
Move the cursor to the third row on page 2 under “setup 2” interface. Press “ ” key
and enter calendar clock adjustment setup interface. It displays as follows:
6.5.3.2 Choice of frequency weighting for AC output
6.5.3.3 Auto-off function
6.5.3.4 Overrun alarm function
6.5.3.5 Baud rate
6.5.4 Calendar clock adjustment
Amplitude of AC output
The upper limit sound
pressure when maximum
output with no distortion
31mV/Pa
1Pa
316mV/Pa
0.1Pa
3162mV/Pa
0.01Pa
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