The DSL-331 is a handheld digital sound level meter with a carrying case, making it more convenient for the user to carry. DSL-331 is suitable for various places. Applicable places: measuring environmental noise, measuring product ultra-quiet, measuring product volume standardization, equipment operating sound, hospitals, and confinement centers.Product IntroductionDSL-331 has analog and digital signal output functions which can be used for a long time with external transformer power supply. It can store 32,000 records, download the record data through a USB cable, or display the measured values and records simultaneously on the computer screen. Optional microphone extension cable is 5 meters long. DSL-331 Sound Level Meter Description: The DSL-331 is a feature-rich sound level meter designed for accurate and versatile noise measurement. With auto-ranging capabilities, a 32,000 records data logger, bar graph indication, and compatibility with Windows software, it meets diverse sound measurement needs. The device adheres to international standards, offering precise readings with features like fast/slow time weightings, AC/DC signal output, and overload indication. Keywords: DSL-331, Sound Level Meter, Noise Measurement, Auto Ranging, Data Logger, Bar Graph Indication, Windows Software, Fast/Slow Time Weightings, AC/DC Signal Output, Overload Indication, IEC 651 Type II, ANSI S1.4 Type2.Measurement SpecificationDisplay : 4 digitsSound Level Range : Low :30~80dB / Middle :50~100dB / High :80~130dBResolution : 0.1 dBFrequency Range : 31.5Hz ~ 8KHzAccuracy : ±1.5dB ( 94dB @ 1KHz )Dynamic Range : 50dBFrequency Weighting : A and CTime Weighting : (FAST) 125ms，(SLOW) 1Sec.Product FeaturesDATA LOGGING : 32,000 recordsRECORDING INTERVAL SETUP : 0.1 Sec. ~ 30 Sec.DATA HOLD : MAX HOLD，MIN HOLDOVERLOAD INDICATION : “OVER”，”UNDER”ANALOG SIGNAL OUTPUT : AC/DC Signal，Output from the headphoneAC OUTPUT RANGE : AC=1Vrms(Full Scale)，output impedance Approx. 100ΩDC OUTPUT RANGE : DC=10mV/dB，output impedance Approx. 1KΩCORRECTION METHOD : Knob correction (Side knob adjustment )Product InformationWorking Environment : 0~40°C / 10~90%RH without dew。Storage Environment : -10~40°C / lower than 80%RH without dew。Elevation Limitation : Lower than 1,000 metersMicrophone : 1/2 inch electric condenser microphonePower Supply : DC 9V Battery x1 / 9V transformer (ADP-01) (Optional)Battery Life : Approx. 50 hours (Alkaline battery)Dimension : 275 (L) x 64 (w) x 30 (H)mmWeight : Approx. 275 g (Battery Included)Accessory : Instruction Manual、9V Battery、 Carrying Case、Calibration screwdriver, 3.5Ø plug, Sponge ball, USB Cable, Software Disk x 1