Active Buzzer Unit
Driven by C8550 PHP transistor, this active buzzer unit is well designed and made. It starts to buzz as soon as I/O interface outputs low electric level. An LED is installed to indicate signal after power is on. Easy to use and install.
* Power supply: DC 5V
* Mounting screw: M3
* PCB measurement: 24.8 * 19.3 * 1.6mm
* VCC-> external power GND -> GND OUT -> I/O
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