Before we start making one, lets answer some basic questions like:
1. What is a Metronome and what does it do?
-A Metronome is a device that produces regular ticks (beats).
2. Who invented the Metronome?
-The mechanical Metronome was invented by Dietrich Nikolaus Winkel in Amsterdam in 1812. Johann Mälzel copied several of Winkel's construction ideas and received the patent for the portable Metronome in 1816.
3. What types of Metronomes are there?
a) Mechanical Metronomes
b) Electronic Metronomes ( the one we will be making)
c) Software Metronomes
4. Who uses Metronomes?
-Metronomes are used by musicians when practicing in order to maintain a constant tempo.
5. How is tempo measured?
-Tempo is measured in beats per minute (BPM). Metronomes can be set to variable tempi, usually ranging from 40 to 208 BPM.
6. Why would I want a Metronome?
- If you are a proud owner of an instrument, any kind ( guitar, piano, tuba, trumpet, violine...) you have to have a Metronome in the home. If you don't own any instruments you can use it to make your self fall asleep.
If you decided to build your own Metronome, then lets head to the next step and see what we need for this project!
Step 1: Components
1. 2 x LED ( I used blue ones, but you can use any colour you want)
2. 2 x 22uF 16V polarised capacitor
3. LM 555 Timer Chip
4. 8 pin chip holder (optional, but I suggest that you use it anyway)
5. 250K ohm Potentiometer
6. 3 x 1K ohm Resistors
7. Proto-board ( dots ) (The size of my board is 5cm X 9cm)
8. 9 V Battery clip
9. 8 Ohm Speaker ( Picture 1 and 2)
10. Some thin wire. I suggest you use solid wire for this project ( Picture 3)
11. 9V Battery
All of these components can be bought in you local Electronic shop. Here are some online stores where you can buy all of these components and much much more!
Lets move on to the next step and see what Tools we need!
Step 2: Tool
1. Wire Insulation Stripper Pliers (To pull of the insulation of the wires) (picture 1 and 2)
2. Wire Cutting Pliers (picture 1 and 2)
3. Needle Nosed Pliers (picture 1 and 2)
5. Third/Helping hand with magnifying glassed (Optional) ( I used one of these because it really helps when it comes to soldering )
6. Desoldering tools:
a) Desoldering pump
b) Desoldering Wike
( In case we make a mistake while soldering) (picture 1 and 4)
7. Soldering Iron (picture 3)
8. Hot Glue Gun (picture 5)
Step 3: Schematic
As you can see right away, the hearth of this project is the LM 555 timer chip.
( the 3rd drawing shows the functions of the 555 timer chip pins)
Our Connections are:
-Pin 1 of the chip is connected to pin 6 via the 22uF capacitor. Pin one is also the base ( 0 V supply)
-Pin 2 is connected to pin 6
-Pin 7 is connected to pin 6 via the 250K Potentiometer
-Pin 4 is connected to pin 8
-Pin 4 is also connected to pin 7 via the 1K Resistor
-The speaker is connected to pin 3 via the 22uF capacitor and to pin 1
Later in the Instructables we will go into details and trough all the remaining connections.
Now, lets start making our Metronome !
Step 4: Planning your Metronome
Take the 4 most important components ( Speaker, 2 LEDs, LM 555 chip and the Potentiometer ) and plan where they will be located on your board.
As you can see on the picture below, I put the 2 LEDs on the top, the speaker in the middle, the potentiometer on the bottom and between them the chip.
How will you arrange the components depends on the shape and how long and wide your board is.
Step 5: Connecting everything together
As you can see this step is a bit long with lots of text and pictures, but when you finish this step you should have your own working Metronome.
Make sure to check out all the image notes!
There are a lot of pictures in this step so on the right bottom of every one there is an image note that displays the number of the photo.
Lets get started ! ! !
* Take the 8-pin chip holder and place it on the board where you want to solder it and solder it. Note where the little curve is, it is important that you place the chip in the right direction. (pictures 1 and 2)
* Cut a small piece of wire, about 4cm and strip the insulation of the ends. (picture 3)
* Use the wire to connect pins 4 and 8 by soldering them. (pictures 4 and 5)
* Take another small piece of wire, also about 4cm with stripped ends and use it to connect pins 2 and 6 by soldering it. (picture 6 and 7) (You should get something that looks like in picture 8)
* Use the 1K ohm resistor and solder it to pins 4 and 7. I soldered one end of the resistor to pin 4 directly and the other end I soldered to one end of the wire and ran the wire to pin 7. (pictures 9, 10 and 11)
* Take the potentiometer and solder it to the board ( picture 12 ) The potentiometer runs from pin 7 to pin 6. Take small pieces of wire and use them to connect the pins from the potentiometer to the pins of the chip holder. (pictures 12, 13, 14 and 15 )
* Lets take our capacitor (picture 16) and solder its longer pin to pin 6 on the chip holder and its shorter pin via a wire to pin 1. (pictures 17, 18 and 19) (You should get something that looks like in picture 20)
* Take the 9V battery clip and solder the RED wire to pin 8 and the BLACK wire to pin 1. (pictures 21and 22)
* Now it's time to mount our 2 LEDs. My LEDs are going to be on the top of the board so I am running a wire from pin 8 to the upper part of the board. (pictures 23 and 24)
* The next step is to solder the 1K resistor to the wire. (picture 25)
* Take the LED and put it so that you connect the end of the resistor to the longer, positive pin of the LED. (picture 26)
* Next step is to connect the negative, shorter end of the LED to pin 3 via a wire. Than to that same connection add a resistor. ( pictures 27 and 28)
* Add the second LED by connecting the longer, positive pin to the other end of the resistor and the shorter, negative pin to pin 1 of the chip holder via a wire. (pictures 29,30 and 31)
* Now lets take the second 22uF 16V capacitor and solder its longer, positive pin to the connection where the first LED and the second 1K resistor join. ( pictures 32 and 33). Leave the negative, shorter pin of the capacitor hanging for now. (picture 33)
* It's time to take the 8 Ohm speaker and solder 2 wires on each pin of the speaker. The wires should be about 10cm long. ( pictures 34, 35 and 36)
* Take the wire that is soldered to the negative pin of the speaker and solder it to pin 1 of the chip holder ; Take the wire that is soldered to the positive pin of the speaker and connect it to the negative pin of the capacitor that we left hanging. (pictures 37 and 38)
* Now that you have everything soldered together it is time to put in the LM555 timer chip. (pictures 39 and 40)
Lets move on to the next step and test our creation !
Step 6: Testing and Troubleshooting
You should get regular beats from the speaker.
When you hear the first beat 1 LED should light up while the other is off. When you hear the second beat the LED that was on should go off and the other that was off should light up.
By turning the potentiometer the BPS ( Beats per Second) should increase or decrease, depending on witch way you turn the knob of the potentiometer.
- Make sure that you put in the chip the right way.
- See if the speaker is wired correctly.
- The capacitor may be connected in reverse. It is important for the positive, longer or negative, shorter pin of the capacitor to be connected where it should be.
- Make sure that you connected the potentiometer like it should be. Once I soldered the potentiometer wrong and the circuit did not work. By quick reconnecting I got the circuit working.
- See if the battery clip is connected like it should be. Red wire to pin 8 and Black wire to pin 1, not the other way around.
- If just one LED is not working, its polarity is reversed so you need to unsolder it and reverse the pin configuration.
If you have a problem and you checked all these above, fell free to send a PM or leave a comment below regarding your problem!
Step 7: Optional
This step is just for enhancing and making your Metronome more appealing and practical.
* Because the Metronomes potentiometer will be constantly used, to make sure that the 3 solder connections don't fail I added some hot glue on the bottom to make it stick to the board. (picture 1)
* You can take a small piece of thin wood board or as i used a small piece of the solder board that was left and hot glue it to the bottom so that you make your Metronome stand. For this, it is very helpful to have the third hand as you can see in the picture. (pictures 2 and 3)
* You can take your insulation tape or duck tape and cover the back of the Metronome where all the connections are. This is good in case it gets in contact with water in any way. I first put the tape but didn't really like how it looked. Fortunately I found out that my Metronome fits perfectly in an old Floppy box. (picture 4)
Step 8: Done!
You have your own electronic Metronome that you build yourself!
This makes a great gift for for anyone who plays an instrument.
Thank you for viewing my Instructables!
Please rate and leave a comment!
If you have a any questions or suggestions on how to improve the Metronome, feel free to send me a message!