How to build a metronome

Most of you know metronomes from sitting at the piano as a child grinding through your hour long practice. A metronome as defined by wikipedia is "any device that produces a regulated audible and/or visual pulse, usually used to establish a steady beat, or tempo, measured in beats-per-minute (BPM) for the performance of musical compositions. It is an invaluable practice tool for musicians that goes back hundreds of years." These instructions explain how to build your own metronome. All the materials you need can be found at your local electronics store.

Here's what you need:

1. 555 IC
2. 3x 1K Ohm Resistor
3. 2x 22uF 16V Capacitor
4. 9V Battery
5. 8 Ohms Speaker
6. 250K Ohms Potentiometer

Despite this project's perfect simplicity I still struggle to understand the scheme. Thankfully, he includes pictures with all the instructions and finishes off with a couple of videos. This metronome can be adjusted to various speeds by changing the resistance. Grab your guitar and play along.

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