Step:
1. The parts we need in this project.
![](https://cdn.hackaday.io/images/5276451583387506852.png)
![](https://cdn.hackaday.io/images/8637271583387519192.png)
![](https://cdn.hackaday.io/images/8473201583387532001.png)
![](https://cdn.hackaday.io/images/2870141583387540274.png)
![](https://cdn.hackaday.io/images/8354701583387548435.png)
![](https://cdn.hackaday.io/images/7154371583387557384.png)
![](https://cdn.hackaday.io/images/3968001583387563225.png)
![](https://cdn.hackaday.io/images/3472041583387569886.png)
2. Some steps to make this circuit.
![](https://cdn.hackaday.io/images/9435941583387593266.png)
![](https://cdn.hackaday.io/images/1923951583387602198.png)
![](https://cdn.hackaday.io/images/7856741583387614247.png)
![](https://cdn.hackaday.io/images/4973671583387621078.png)
![](https://cdn.hackaday.io/images/5875211583387628307.png)
![](https://cdn.hackaday.io/images/1389701583387637890.png)
3. Test the buzzer, then add the led to test the indicator.
![](https://cdn.hackaday.io/images/5643391583387651935.png)
![](https://cdn.hackaday.io/images/1928111583387659946.png)
![](https://cdn.hackaday.io/images/5647081583387667781.png)
Components list
(1.) 12V Relay https://www.utsource.net/itm/p/1870494.html
(2.) Capacitor 25V 2200uf https://www.utsource.net/itm/p/9509010.html
(3.) Capacitor 25V 1000uf https://www.utsource.net/itm/p/9506441.html
(4.) Buzzer https://www.utsource.net/itm/p/8027891.html
(5.) Resistor 220 Ohm https://www.utsource.net/itm/p/6491244.html
More details, pls check the video on Youtube: