<p><br><br>&nbsp; 1. It is compatible with the traditional active buzzer function and is synchronized with the flight control unit. The three-stage remote control switch can be used to control the buzzer.<br><br>&nbsp; 2. When the flight control is normally connected, if the drone's main battery is disconnected, it will automatically emit 90 decibels of sound after 30 seconds of battery failure, the sound is much larger than the normal buzzer, and white LED blinks continuously.<br><br><span style="font-weight: bold;">To turn the buzzer on or off:</span></p><p><br>Press and hold the home button for more than 2 seconds and hear the "1-2-3" sound that indicates the buzzer has started.<br>Press and hold the start button for more than 2 seconds. After hearing the "3-2-1" sound, the buzzer turns off.<br>The buzzer is compatible with all F3 / F4 / F7 flight controllers based on Cleanflight / Betaflight, and can operate as long as it is connected to the buzzer interface of the flight controller. When the flight control wiring is correct, the multi-rotor aircraft is turned on and the flight control power supply will automatically charge the buzzer battery.</p><p></p>