Introduction: Metronome

Picture of Metronome

So, you have built an electric cigar box guitar and started to get playing, only to realize that you don't know how. In fact, you can't even keep time. Your playing keeps getting faster and slower. It sounds like you need a metronome. A metronome is a device that helps you keep a steady time when you are playing an instrument by making a tick at a regular interval that you pre-set. If you have a little bit of electronics knowledge, it is very simple to build an electronic metronome.

Step 1:

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- TLC555/TLC555CP LinCMOS Timer (8-Pin DIP) (Model: TLC555/TLC555CP | Catalog #: 276-1718)
- (x2) 10µF 35V 20% Radial-lead Electrolytic Capacitor (Model: 272-1025 | Catalog #: 272-1025)
- 10K-Ohm Horizontal-Style Trimmer (Model: 271-282 | Catalog #: 271-282)
- 1K Ohm 1/4-Watt Carbon Film Resistor (Model: 271-1321 | Catalog #: 271-1321)
- (x2) Red LED with Holder (Model: 276-084 | Catalog #: 276-084)
- 8-Ohm Mini Speaker (Model: 273-092 | Catalog #: 273-092)
- 500K Ohm Volume Control with Push Switch (Model: 271-002 | Catalog #: 271-002)
- Hexagonal Control Knob (Model: 274-407 | Catalog #: 274-407)
- Multipurpose PC Board with 417 Holes (Model: 276-150 | Catalog #: 276-150)
- Project Enclosure (5x2.5x2") (Model: 270-1803 | Catalog #: 270-1803)
- Fully Insulated 9V Battery Snap Connectors (Model: 270-325 | Catalog #: 270-325)
- Enercell® Alkaline 9 Volt Battery (Model: 23-853 | Catalog #: 23-853)

Step 2: Build the Circuit

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Build the circuit according to the schematic, with the exception of the LEDs, the speaker, 9V battery connector, and the potentiometer. Those will be wired in later.

Step 3: Wire the Pot

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Wire a black wire to the center pin on the side of the potentiometer and a red wire to the right pin.

Wire a red wire to the center pin on the bottom of the potentiometer. Wire another red wire to either of the side pins.

Step 4: Mark and Drill

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Flip the case on it's side and measure 3/4" in from each side. Center both of these holes along the other axis. Drill them both with a 3/4" drill bit.

Step 5: Insert LEDs

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Install your LEDs into the case and fasten them in place.

Step 6: Mark and Dril More

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Flip your case up on its small side and make a perfectly centered mark. Drill a 3/8" hole using the mark as a guide.

Step 7: Potentiometer Time

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Install the potentiometer into the 3/8" hole in the side of the case.

Step 8: Draw a Star

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On the side of the case with the LEDs, make a mark that is dead centered. Make two 1/4" spaced marks to each side of this center mark to make a plus. Make two more similar marks at each 45 degree diagonal to form a star pattern.

Step 9: Drill

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Drill through all of these marks with a 1/8" drill bit.

Step 10: Wire It Up

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Wire the LEDs and the speaker to the board as shown in the schematic.

Wire the side connections of the potentiometer to the board as the potentiometer shown in the schematic.

Wire the red wire of the 9V battery connector to one of the red wire on the bottom of the potentiometer. Wire the other red wire from the potentiometer to power on the circuit board.

Finally, wire the black wire of the 9v battery connector to the ground plane on the circuit board.

Step 11: Glue

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Hot glue the speaker to the inside of the case in front of the star pattern. The speaker should be able to cover all of the holes when you look at it from the outside.

Step 12: Power

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Plug in the 9V battery to power up the circuit. It might now turn on. If it doesn't turn on, press down on the potentiometer knob to engage the power.

Turn it off.

Step 13: Case Closed

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Fasten the case closed with screws.

Step 14: Knob

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Attach the knob to the potentiometer shaft to finish it off.


stoptime1 (author)2014-01-02

how can you solder the wires when you never see the bottom where they connect

matchbox (author)stoptime12015-04-11

you need to view the schematic diagram where the components connected it will help and guide you..

matchbox (author)2015-04-11

Wow! Finally, I found a good circuit for my metronome. I have practiced playing guitar and i am sure this device could help to improve my timing and speed skills ;).. Instead of buying one i decided to make.. thanks for sharing. :)

BrendanTheSequeira (author)2015-02-01

if i want to replace the 2 leds with a motor ......what do i have to change?

jzs2 made it! (author)2014-09-05

I just finished this project a few hours ago. I had started this project a few years back but I only had time now to finish it.

jzs2 made it! (author)2014-09-05

I just finished this project a few hours ago. I had started this project a few years back but I only had time now to finish it.

CarterBond (author)2014-01-12

I bought the parts to be able to this project. I noticed you used a 10k resistor instead of the trimmer. Since I already bought the parts would I just solder the bottom two connections on the bottom of the trimmer and leave the stop free or should I go and get a resistor? If you could get back to me that would be great, thanks.

stoptime1 (author)2013-11-30

where does the horizontal trimmer go the pictures don't show it being used

ajb746 (author)2013-08-02

In the parts list it says "10K-Ohm Horizontal-Style Trimmer", but I don't see that anywhere else in the instructable. Is it really needed, or can i just use 10k resistors?

ajb746 (author)2013-08-02

I tried this several months ago and it didn't work out, but now i have way better tools and more knowledge with electronics. I'm going to try it again, hope it works!

quatchiguy (author)2013-07-31

Great Instructable! Mine turned out great!

randofo (author)2013-07-29

Should be fine.

wkennedy (author)2012-12-28

i just built this circuit according to the schmatic and it seems to swing slightly... is there a way to correct this? if you are going to play with a metronome you need everybeat to be the exact length, not everyother one to be slightly shorter...i was reading online about getting the 555 to output a 50% duty cycle, but i cant seem to translate that into building this metronome! any idea? or maybe im making it up and it is perfect :p

corradini (author)2012-02-01

I'm in the middle of building this - and thanks SO much, by the way! Assuming I ever succeed, my boys (learning piano now) will love it - and I'll score points as the cool geek dad...

SO - it would be SO helpful if you could also supply a physical wiring diagram (beg, beg?) for the actual PC board? (MAKEzine does this - it's VERY helpful!) I know it's a short hop for electronics whizzes from the schematic - but hey, they don't need the instructable, either, if it comes to that!

I totally get the schematic, conceptually, but when it comes to figuring out how these 3 things all connect and then are connected to the ground bus, etc. - I'm pulling my (little remaining) hair out. I'm TRYING to guess from your photos, but that's maybe 40-50%, and even then it's maddening...

MAJOR thanks if you can help!

sreggy (author)corradini2012-06-13


sreggy (author)2012-06-12

please help... just like dsmith said can the 10k ohm resistor be used to replace the trimmer mentioned in the parts list? Really want to start soon but don't want to screw it up

Backpackboy (author)2012-05-01

Good!!! ovservationnn But we Adjust the metronome in an Similar or same tempoo!!

dsmith84 (author)2012-04-24

your parts list has a 10k ohm horizontal trimmer, but instead you used a 10k ohm resistor. Would the trimmer have done anything that the resistor couldn't do? Just wanted to clarify this part before I started building.

BTW, somebody12345 the total cost was about 30$, unless you have a buddy at RadioShack who can let you use his discount, it brings the cost to 17$

somebody12345 (author)2012-03-14

what is the total cost?

MrGreenFingers (author)2012-02-15

Great Instructable :) ...Have built it, and now adapting it to a machine of mine.|
Only one question though, Is it possible to set the Tempo? or timing? ... with a rotary switch or something? Im not too tech-savy... so any help would be greatly appreciated. Thanks. MGF

randofo (author)MrGreenFingers2012-02-16

The potentiometer should control the tempo.

randofo (author)2012-02-16

Both 1K resistors meet with the plus side of the capacitor and pin 3 on the chip.

randofo (author)2011-10-01

The wires on the bottom of the potentiometer act as a power switch between the circuit board and the battery connector.

If your LEDs are lighting up and not blinking, it means that your board is getting power, but the 555 chip is not work as it should. This could mean the LEDs are getting power from something other than the 555 chip.

Have you connected pin 4 to power? Have you connected together pins 2 and 6?

Does the chip get hot to the touch when you plug in the power?

Are there any connections underneath the board accidentally crossed?

My recommendation at this point would be to rebuild the circuit on a breadboard (if you can) and see if you can get it working there first. If that is not possible, check all of your connections really carefully against the schematic. Make sure that polarized parts were not wired in backwards.

It is hard for me to tell at the moment from these pictures alone.

Bruno153 (author)2011-07-12

I reaaaally woud like to see this working on a video.... BTW, nice project!

mdog93 (author)2011-07-10

only thing is if you're following music with a particular timing- how are you going to know what tempo the metronome is set on.

bowmaster (author)2011-07-09

How slow and how fast can it go?

randofo (author)bowmaster2011-07-09

It can go both much too slow and too fast to be useful for musical timing. You can tweak this by changing the value of the 10K resistor and 500K potentiometer.

jensenr30 (author)2011-07-07

i'm loving your Inst'ables recently!

vishalapr (author)2011-07-07

Very well explained and very nice quality photos!!!Well done!
Rated 5*****

About This Instructable




Bio: My name is Randy and I founded the Instructables Design Studio. I'm also the author of the books 'Simple Bots,' and '62 Projects to ... More »
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