Feature: The Power Supply Input is For The Backlight for DC/AC 5-12V 0.1A R1 And R2 Adjustable Resistance for Adjust Pointer jump Performance: temperature 2%, humidity 70%, if there is no difference in the test results, it can run at normal temperature and humidity. Pls Notice :The Connect cable need you welding on the Driver board Debugging method: Method 1: Connect the power amplifier with the signal generator 1KHZ signal, adjust the volume of the power amplifier to the maximum, adjust the adjustable resistance, so that the meter pointer points to the 0 position Method 2: No signal generator, you can use mobile phone to download the signal generator software, use the mobile phone to output 1KHZ signal to the power amplifier, adjust the power amplifier volume to the maximum, adjust the adjustable resistance, so that the meter pointer points to the 0 position Note: Please allow 1-5mm errors due to manual measurement. Due to light and screen setting difference, the color of the item may be slightly different from pictures. Specification: Color: Silver Material: Stainless Steel Light Color: White, Yellow Size: 15.5x4.8x3cm(6.11x1.89x1.18Inch) Quantity: 1pc Note: And due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Included: 1 x VU meter