GRAS 42AG
Multifunction Sound Calibrator, Class 1
Sound pressure level: 94 dB or 114 dB
Frequency: 250 Hz or 1 kHz
ANSI: S1.40
IEC: 60942 class 1
GRAS Sound & Vibration A/S
Skovlytoften 33, 2840 Holte, Denmark
www.gras.dk
The GRAS 42AG Multifunction Sound Calibrator is a
portable, battery-operated precision microphone
calibrator. The calibrator can be used directly on 1"
microphones. Adapters for calibrating 1/2" (factory
mounted), 1/4" and 1/8" microphones are included.
Technology
The GRAS 42AG Multifunction Sound Calibrator is a
portable, battery operated sound source for calibration
and check of microphones and sound level meters. It is
designed for field use and comes with a protective casing.
It conforms to the requirements in IEC 60942 for a class 1
sound calibrator.
It can produce a sinusoidal signal of 250 Hz or 1 kHz at 94
dB or 114 dB. For documentation purposes, 42AG provides
display of the environmental conditions: ambient air
pressure, temperature.
The sound is generated by a small loudspeaker integrated
in the acoustic coupler. An internal reference microphone
measures the level in the coupler and a feed back circuit
automatically adjusts the level. Therefore, the calibration
level is virtually independent of ambient conditions like
temperature, atmospheric pressure and humidity within
the specified range of operation.
The calibrator has been designed to serve 1” and smaller
microphones and sound level meters equipped with such
microphones. 1” microphones fit directly in the calibrator
coupler, while 1/2”, 1/4” and 1/8” microphones are served
by application of adapters that are part of the delivery.
The calibrator is powered from two type LR03 alkaline
batteries (AAA-size). lf the voltage supplied by the
batteries is too low to ensure proper operation, the
calibrator will automatically switch off or not switch on.
Benefits
42AG is designed to fulfil the need for a portable and
versatile calibrator for field use. Also, it is designed to be
the logical replacement or upgrade from existing
calibrators.
42AG represents improved functionality and user
friendliness. Its combination of portability, automatic level
adjustment and two calibration frequencies and levels
makes it a complete and self sufficient solution that can
be used to perform a complete field-verification without
the need for other instrumentation, e.g. for recording
ambient calibration conditions.
With two calibration frequencies, 250 Hz and 1 kHz it is
well suited for calibration of microphones that normally
Date 30-03-2018.
GRAS 42AG Multifunction Sound
Calibrator, Class 1
Page: 2
are calibrated at 250 Hz as well as sound level meters
which normally are calbrated at 1 kHz.
42AG can calibrate at two different levels, 94dB and 114
dB. The 114 dB is a level that suits microphones with
medium sensitivity, while the low level of 94 dB makes it
possible to calibrate microphones with high sensitivity
without overloading the microphone.
Specifications
Page: 3
GRAS 42AG Multifunction Sound
Calibrator, Class 1
Frequency
Hz
250 (251.19 ± 0.30 Hz) or 1
kHz (1000 ± 1 Hz)
Sound pressure level
dB
94 (± 0.2 dB) or 114 (± 0.2
dB)
ANSI standard
S1.40
IEC standard
60942
Temperature range, operation
°C / °F
-10 to +50/14 to 122
Battery type
LR03 (AAA)
CE/RoHS compliant/WEEE registered
yes/yes/yes
Weight
g / oz
125
Level and frequencies at reference conditions (23,0°C/101,325 kPa/50% Relative Humidity) - levels in decibel relative to
20 µPa.
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.
Date 30-03-2018.
Ordering Info
GRAS 42AG Multifunction Sound
Calibrator, Class 1
Included items
GRAS RA0023
1" microphone coupler
GRAS RA0297
Adapter for ½" microphones.
GRAS RA0049
Adapter for ¼" microphones
GRAS RA0069
Adapter for 1/8" microphones
GRAS EL0001
Four LR6-AA alkaline cells
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.
Date 30-03-2018.
Page: 4
We Make Microphones
Tradition
Innovation
Quality
Since the establishment in 1994,
GRAS has been 100% dedicated to
developing and manufacturing
high-quality measurement
microphones and related acoustic
equipment.
We work with everybody with an
interest in sound or noise within
the fields of aerospace,
automotive, audiology, consumer
electronics, noise monitoring,
building acoustics and
telecommunications.
At GRAS we know that in order for
you to trust your measurement
results; signal quality, stability and
robustness are essentials. We
design and build them to perform
under real life conditions – and
beyond.
GRAS Sound & Vibration A/S
Skovlytoften 33, 2840 Holte, Denmark
www.gras.dk
Download PDF
Similar pages