How to use:
1. Install the battery, press the switch in the middle. Green LED lights, the tester is ready to work.
Press the switch again, LED is on; press one more time, LED is off. Press for two seconds, tester sounds DD, then turn off.
When no electric field signal is detected, the tester is with green LED, it will automatically turn off in 5 minutes.
2. When detects voltage, tester tip sounds with red LED; when electric field becomes stronger, the tester is with faster sound.