How to Make a Metronome

Intro: How to Make a Metronome

Hi everyone, this is my first instructable. I hope you enjoy it!

In this instructable I will show you how to easily make an electronic metronome, at the heart of which is a 555 timer. I found the original plans for this and the circuit diagram here.

Here is a video of the metronome.


It has two LEDs and a speaker. For each beat, it clicks and switches the LED that is lit up. You control the speed of the beats with a dial.

Step 1: Parts and Tools

There are a few parts and tools you'll need you'll need. I found all of the parts at Radioshack, and I bet that all of the tools can be found there too. Links are to the parts and tools at RadioShack.com.

Parts:
9v battery snap-on connector
9v battery
2 (two) 22 uF capacitors
3 (three) 1K ohm resistors
Perforated PC board
555 timer
Wire
SPST Switch
2 (two) 3V LEDs
8 Ohm Speaker (see notes below)
250K Ohm Potentiometer (see notes below)
Knob
And finally... a project box.

Notes:
A project box can be just about anything that the parts will fit into, will sufficiently protect what you've built, and have some way of providing access to the controls. I used a see-through plastic box that held thumbtacks. It conveniently opens and closes for repairs and battery changes, makes it look cool, and you can easily drill holes for the controls to go through. You could buy a project box from Radioshack or find one in your house.
About the speaker: I found mine in a bad set of walky-talkies. To find out the resistance, just take a multimeter and measure the resistance across the leads or it should say on the package if you bought it. It needs to be 8 ohms!
About the potentiometer: If you click on the link, it won't take you to a 250K ohm potentiometer. That's because Radioshack doesn't have one. Instead, I found a stereo 100K pot at Radioshack and the two signal paths in sequence so it became a 200K pot (which is close enough). The diagram for this is in the next step.

Tools:
Drill (if you want/need to drill holes in your project box for the controls/leds/speaker)
Soldering iron
Glue/adhesive to hold stuff in place in the project box (I used a hot glue gun, it's easy to use and holds things well)
Breadboard (if you want to make a prototype, which you should)

Step 2: Prototype

In this step I will show you how to make a prototype of the metronome.

Basically, just follow the picture below to put the circuit into your breadboard and wire it up! You can add in the switch at the +9v input or at the ground output. I used ground. Make sure to get the polarities on the capacitors and on the LEDs right! If it doesn't work, double check your connections and then make sure that the LEDs and the pot and all of the parts work. If you turn it on and it doesn't work, turn it off and make sure that no parts are hot. If any are, you may have fried them with a short or by putting them in backwards. If you are using the stereo pot, check out the wiring diagram for that below.

Step 3: Solder!

So you have assembled your parts and tools, prototyped the metronome on a breadboard, and now you will be assembling the circuit. This is where you use the soldering iron! When I solder a PC board, I always draw a diagram on graph paper so I'm not making it up as I go along. It makes things a lot easier.
Make sure to use as little solder as possible. I didn't and I had to start over. Luckily I wasn't very far and I had more PC board. Also remember that when you flip over the PC board the pins on the IC are flipped over too, and that you should make the wires to your components longer than you need them just in case you have a problem with the project box.

When your done, test it! If it doesn't work, check your connections, check the battery, check polarities. If everything's right, you may have damaged something during soldering by overheating it.

Make sure to cut your PC board down to size. A sharp hobby knife works well. You can either cut your PC board to the smallest you can get it, or to the perfect size for your box. I cut it to the smallest I can get it and it works fine.

Below is a scan of the diagram I drew on graph paper, and the picture of the circuit diagram. Sorry my drawing is so messy, you don't have to use it, you can make your own layout. (Warning: I checked it, but I haven't thoroughly checked my drawing...so you may want to double check the circuit!)

Step 4: Assemble the Project

This is the final step. You will be putting your project in the project box. First, you will need to make sure that everything fits in the project box. Don't drill any holes yet, just put everything there and decide the layout of the project (where you want your holes, where the PC board and batteries go, etc.) Double check that it works and that everything fits and you can access all of the controls if they are where you want them to be. Don't forget to drill holes for sound from the speaker to go through!

Next, get all of the right sized drill bits for each component, and drill your holes. Don't press too hard on the drill! I broke my case twice because I pressed down too hard when drilling.

Put everything in it's hole and screw into place the pot and switch. The pot probably has a little protrusion that you'll need to drill a little hole for right next to the big hole. This is to keep it from twisting around when you turn the knob.

And finally, hot glue your speaker and LED's!

Congratulations! You just made your own metronome! Now go show it off to people. But don't show it off in an airport.

Share

Recommendations

  • Metalworking Contest

    Metalworking Contest
  • Tiny Home Contest

    Tiny Home Contest
  • Audio Contest 2018

    Audio Contest 2018

38 Discussions

0
None
C4mpi59

Question 14 days ago

Is that a linear potentiometer?

0
None
elkaddalek

3 years ago on Introduction

I need a more simple diagram, I tried using this diagram & nothing happened. Except for one of the LEDs burning out & no sound on the speaker. I know nothing about reading circuit diagrams & even lesser about the parts, what to use & what side to connect, positive, negative ex.

Can you explain the wiring for 3 pin potentiometer and how it is connected with the resistor above it (as in circuit diagram)?

0
None
jacobr8893

6 years ago on Introduction

I've made it, but yours and the one i have made both have this sort of strange pseudo-swing in the tempo. Is there any way to get rid of that? It would be more accurate.

0
None
gbear_01

8 years ago on Introduction

I have followed this instructable, but I am using a SE555 timer I got from DigiKey. The volume coming out of my metronome is so low it is basically unusable for a musical aid. Any ideas to boost the volume?

1 reply
0
None
sjoobbanigbear_01

Reply 7 years ago on Introduction

Higher voltage, or instead of a speaker, add a female 3.5 MM port, and connect that to speakers

0
None
sjoobbani

8 years ago on Introduction

What about a 500K ohm knob thing? and do I really need a speaker? I mean... could I connect it to a relay (that isn't connected to anything else) so it just makes the noise? I need a reply quick! I'm trying to go get the stuff real soon!

1 reply
0
None
gbear_01sjoobbani

Reply 8 years ago on Introduction

any potentiometer that has a higher resistance than the one specified will do, it will just "drop out" much sooner in its rotation.

0
None
oliboy_48

8 years ago on Introduction

what if i want to connect an earphone output...how and where will i place it?..i'm planning on using it for my drum playing...thanks..

1 reply
0
None
vignesh1230oliboy_48

Reply 8 years ago on Introduction

Do you mean instead of the speaker? If so just get a stereo/mono jack and solder it in place of the speaker.

0
None
TSC

8 years ago on Introduction

Sweet, I wish I could build  this!!!!!!!!!

0
None
raykholo

9 years ago on Introduction

this can be made a lot cheaper -- simply with a relay and the potentiometer , which i understand to be an adjustable resistor... wire the battery to the relay so that it switches between the 2 contacts and use the potentiometer to control how fast or slow.. and use leds as used here..

1 reply
0
None
Padlockraykholo

Reply 8 years ago on Introduction

Incorrect. You would have to use at least two relays, and you could not control the speed.