The voice recorder "SOROKA-04M" is designed to record an audio signal in mono mode from a built-in or external digital MEMS microphone to a microSD or microSDHC Class4 or higher memory card. Main technical characteristics:
File system type - FAT32;
Recorded file format - "WAV";
Maximum file size - 2 GB;
The audio stream speed at a sound sampling frequency of 16 kHz is 256 kbps;
The accuracy of the built-in clock is not worse than ± 1 minute per month;
Battery charging time - no more than 3 hours (typical 2.5 hours);
The number of configurable timers from 1 to 5 (set by the user);
Acoustic start mode;
The ability to encrypt recorded files;
Overall dimensions 60x33x14 mm;
Operating time from the built-in battery according to the table:
Sound sampling frequency Acoustic trigger mode Recording mode Operating time 16 kHz on mono from 17 to 100 hours off mono not less than 17 hours 8 kHz on mono from 32 to 100 hours off mono not less than 32 hours
Audio path parameters:
Range of operating frequencies at the level of minus 3 dB:
(100 - 7000) Hz at an audio sampling frequency of 16 kHz; (50 - 3500) Hz at an audio sampling frequency of 8 kHz;
ADC scale resolution 16 bits;
Range of manual gain control from minus 12 to +18 dB in 6 dB increments;
Range of automatic gain control from minus 12 to +18 dB in 6 dB increments;
The sound threshold for turning on the voice recorder in the acoustic trigger mode is set using manual gain control;
The nonlinear distortion coefficient of the voice recorder, when operating from an internal/external microphone, is no more than 1%, for an audio signal with a frequency of 1 kHz and a sound pressure level of 94 dBA;
Suppression outside the operating frequency band with octave tuning is not less than 60 dB;
Sensitivity of the microphone input is not less than minus 23 dBFS when feeding an acoustic signal with a frequency of 1 kHz and a level of 94 dB SPL;