Cirrus Optimus Green Series, Instrument Hanbook

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Optimus sound level meter - instrument handbook
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The microphone should be parallel to the body of the calibrator. Also ensure that the
small bleed-hole next to the microphone cavity is not blocked as this could cause
damage to the microphone.
Your Optimus sound level meter will automatically make adjustments for the level
produced by the acoustic calibrator and the microphone type fitted to the instrument.
9.2.1 Background noise
In order for the calibrator to operate as intended, the ambient acoustic noise level
should be no greater than 80 dB(A).
9.2.2 Stabilisation
In order for the sound pressure level and frequency to stabilise after switching the
calibrator on when coupled to a microphone, a period of at least 3 seconds should be
allowed before performing a calibration.
9.3 Changing the battery
The CR:514 and CR:515 acoustic calibrators use a single 9 V alkaline battery. This type
of battery is known as 6F22 or NEDA 1604. It is also commonly known as PP3.
Battery Compartment
Retaining Screw
Battery Cover
Battery