$1 Bike Bell

On Amazon.com, the average bike bell costs five to eight dollars. This bell is much cheaper and takes only about 20 minutes to make. It's very simple; even beginners can make it with a breeze.

Parts and tools

A buzzer is used to make sound (only active buzzers will work, because it only needs DC voltage to function). The button is used to trigger the sound. Any battery will work, but I recommend using a coin cell battery, because they are small and use 3V, enough to make a loud enough sound. A soldering iron is used to connect the pieces on a PCB.

Installation

I attached the battery to the back of the PCB using hot glue, but tape will work too. It is unlikely you will need to replace the battery for a long time, because the buzzer does not use much power and is not on for a long time. Without the button being pressed, battery is not being used.

The wires are on the bottom, making it aesthetically pleasing. To attach it to your bike, put a strip of tape around the area you will put the device on. Then apply hot glue over the tape and put the bell on top of the glue. This will allow you to be able to take it off if necessary without much hassle, but will stay firmly attached to the bike when riding.