1. Introduction
The Sound Level Meter is widely used in noise engineering work, quality control, health care, and other environmental measurements. Applications include science and industry, and it is used in homes, offices, schools, businesses, and road construction.
2. Features
This instrument is a high-precision sound level meter with an accuracy of up to +/-1.5dB.
- Measurement range: 30-130dB.
- Frequency weighting: A weighting.
- Maximum and Minimum value hold function.
- Data Hold function.
- Red backlight alarm and sound alarm.
- Auto or manual power off function.
- Temperature measurement function.
- Temperature Unit (°C/°F) selection function.
3. Specifications
| Parameter | Specification |
|---|---|
| Measure range | 30~130dBA |
| Accuracy | ±1.5dB (reference SPL point at 94dB@1KHz) |
| Weighting | A weighting |
| Frequency range | 31.5Hz-8.5KHz |
| Sampling rate | 2 times/second |
| Data Hold | Maximum and Minimum hold |
| Digital display | 4 digits |
| Resolution | 0.1dB |
| Temperature measurement range | -10°C ~ 50°C (14°F ~ 122°F) |
| Temperature Accuracy | ±2°C |
| Temperature Resolution | 0.1°C |
| Microphone | 1/2 inch Electret Condenser Microphone |
| Power supply | AAA size battery X 3 pcs |
| Battery Included | No |
| Certification | CE |
| Origin | Mainland China |
4. Package Contents
The product package typically includes:
- 1 x Digital Sound Level Meter (ST9604)
- 1 x Wind Shield Ball (pre-installed or separate)
- 1 x User Manual
5. Setup
5.1. Outlook of the Unit
- ECM microphone and wind shielding ball
- LCD display panel
- Power On/Off key
- Minimum and Maximum value hold key
- High and low SPL alarm setup key
- Temperature unit (°C/°F) key
- Battery door
5.2. Battery Installation
Before use, open the battery door located at the back of the unit. Insert three (3) AAA size batteries into the compartment with correct polarity. Close the battery door securely.
If the battery power indicator on the LCD becomes empty [], replace with new batteries to ensure proper operation.
5.3. Wind Shield Installation
Ensure the wind shield ball is properly placed over the ECM microphone to reduce wind noise during outdoor measurements.
6. Operating Instructions
6.1. LCD Screen Description
- SPL value reading
- SPL unit (A weighting)
- Maximum value
- Minimum value
- Value hold
- Timer icon
- Temperature unit
- Temperature reading
- High Alarm
- Low Alarm
- Speaker icon
- Battery Power icon
6.2. Power On/Off
To power on, depress the [Power On/Off] key. All LCD segments will display for 1 second, then the unit enters normal sound level measurement mode, showing the current environmental sound pressure level.
To power off, depress the [Power On/Off] key until the LCD screen turns off.
6.3. Data Hold (Minimum and Maximum Value)
In normal measurement mode, depress the [MODE] key. The display will sequentially freeze the data value with Minimum, Maximum, and real-time values. The screen will show