If the PIR sensor detects some movements it triggers a passive buzzer. Arduino Nano 33 IOT has a WiFi module that is used in this project. Arduino can make a phone call on the smartphone. The WiFi ...

This project demonstrates how to use a buzzer module with an Arduino Nano to produce sound or generate alerts. Buzzer modules can be either active or passive, each requiring different driving methods.

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 ...