1PC realtime monitoring, recording and storage, automatic measuring level range is 30dB ~ 130dB. 2High sensitivity sensor, accurate measurement, fast and sensitive, easy to operate and use. 3Designed to monitor sound quality in various environment, reliable measurement. 4Suitable for noise control engineering, quality control, home environment monitoring, etc. 5Small and compact, lightweight, easy to carry, with high accuracy, durable and longlasting. Item Type: Digital Noise Meter Material: Plastic Color: As shown in the picture Battery: 1 x 9V battery(Not included) Accuracy: 1.4 dB Frequency Range: 31.5Hz~8kHz Dynamic Range: 50 decibels Measurement Level Range: Low Frequency: 30dB~80dB Medium: 50dB~100dB High: 80dB~130dB Automatic: 30dB~130dB Time Weighting: C fast 125ms; slow (1s) Display: 4-digit LCD display with a resolution of 0.1 decibels Sampling Time: 2 times/sec Basic Operation: (1) Open the battery cover, and then install 1x 9V battery in the battery compartment. (2) Close the battery compartment. (3) When the battery power is low, the icon replaces the battery. (4) When using the AC adapter, insert the plug of the adapter into the DC 9V connector on the side panel, and you must take out the 9V battery. (5) Turn on the power of the instrument. (6) Press the "mode" key to select the desired function Instructions: (1) Frequency weighting selection: press "DBA DBC" key to select A or C. (2) Backlight: After turning on the meter, press the "bulb" key, and the backlight will turn on. It will automatically turn off after about one second. No activity for 30 seconds, or you can press the "bulb" key again to disable the backlight 30 seconds before. (3) Hold: After turning on the meter, press the "HOLD" button, the "Hold" icon will appear in the lower right corner of the LCD display, indicating that the data has been frozen. To release the reserved reading, Press the "HOLD" button. (4) Level range selection: Press the "LEVEL" key, the level range will be from "Lo", "Med", from "Hi" to "Auto". (5) Power on/off: Press the "Power" key for 1 second to turn on the meter. Press the power button for about 3 seconds to turn off the meter. (6) Maximim/Min Press the "Maximum MIN" key once to enter the Maximum measurement. "Maximum" will appear in the upper left corner of the LCD display. Will display the maximum sound level captured. Press "Maximum MIN" again and press "MIN" (minimum) will appear on the upper left corner of the LCD display and the lowest sound level will be displayed. Press the "Maximum MIN" button to exit again Maximum / MIN Measurement mode. (7) Fast/slow Press "F/S" to select fast or slow weighted measurement. Fast: Fast sampling and measurement, once every 125ms. Slow: The sampling speed is slow, 1 time per second. (8) Date and time setting (8.1) While turning off the meter, press and hold the "SET" key and keep "SET" while turning on the meter. When the meter is turned on, press this key. Year data, the next to DATE will flash, indicating that you have entered the date and time setting mode.