Wildlife Acoustics sm3bat, User Manual

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SM3BAT User Guide Utilities
page
59
BIOACOUSTIC MONITORING SYSTEMS
9.3
How to Measure Microphone Sensitivity
You can view and verify the sensitivity of acoustic and ultrasonic microphones.
This utility displays dB (re full scale) of both types of microphone.
1. At the Song Meter Main Menu , select Utilities , and press ENTER/MENU .
2. Select Calibrate Mics and then press ENTER/MENU .
MICROPHONE CALIBRATE
@1 @40 kHz
Ch 0: -62.4 -73.8 dB
Ch 1: -62.5 -73.6 dB
a. The values under @1 represent levels at 1 kHz, a good measure of acoustic
sensitivity.
b. The values under @40 are for testing the SMM/SMM-U1 with the available
Ultrasonic Calibrator.
3. Press ENTER/MENU when finished.
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To test SMM-A1 microphones, you can also generate a 1 kHz signal with
a professional microphone calibrator (which slides over the mic), or use
a signal generation smartphone app played in proximity. To set both
microphones at approximately the same sensitivity, adjust the GAIN
level in your program to better match the microphones.
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To test SMM/SMM-U1 microphones, order the Ultrasonic Calibrator.
9.3.1
How to Use the Ultrasonic Calibrator
Use the available Ultrasonic Calibrator for the SM3BAT to calibrate SMM/SMM-U1
microphones. Since ultrasound is beyond the range of human hearing, verifying
proper system and microphone performance can be a challenge. The Ultrasonic
Calibrator helps you test both the microphone and the full recorder system.
The battery door is located at the top of the unit. When the battery can no longer
power the device the LED will not illuminate and no sound will be emitted. The
volume of the emitted sounds will not decrease as the battery is depleted. If the
LED is lit at all, then the calibrator is operating normally.
The calibrator has two modes of operation:
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CAL : Calibration mode is used to test the microphone at close range.
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CHIRP : Chirp mode is used to test the entire system at a greater
distance.