When reed switch is opened, pin 2 of Arduino goes high with the help of the pull-up resistor R2, and the alert signal is available through the piezo-speaker PZ1 (not an active piezo-buzzer). At the ...

Localbuzz This project creates an interactive buzzer system using Java Swing and key events. The program displays a graphical interface where pressing specific keys triggers corresponding actions.

Even though you can drive a logic-level MOSFET directly from the I/O of an Arduino, it’d be better to add a 100-Ω current limiter resistor (R1) in between to protect the I/O. Furthermore, another ...

Posted in Security Hacks Tagged alarm, arduino, arduino mega, gsm, i2c, rfid, security ← Homemade Portable Gold Mining Trommel Soundwave Tunes Up Your Portable Workbench → ...