The SV 36 acoustic calibrator is a small, portable dual-range Class 1 device (sound source). Powered by two LR03/AAA batteries, it contains a loudspeaker producing acoustic pressure of defined level 94 db & 114 dB at frequency of 1 kHz.

Reference piezoresistive sensor for monitoring generated level, pressure and temperature sensors for measurements of atmospheric conditions and a microprocessor system controlling the operation of the calibrator. Sinusoidal waveform of 1 kHz frequency is digitally generated and feeds the loudspeaker. Sampled signal from the reference piezoresistive sensor indicates the level of currently generated signal in a feedback loop. On the basis of information about the level of the signal, actual values of pressure and temperature, microprocessor adjusts amplification of the loudspeaker signal in order to produce appropriate sound pressure level in the calibrator’s chamber.