Turn an Electric Motor Into a Pickup!

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Most toys/gadgets/walkmans/tape players/electronic object that needs something to move will have a motor of some kind inside it. These can be easily turned into pickups thusly...

In this demonstration I made a very basic instrument construction just to show how the pickup is used. I will talk about this in the last step. How you adapt your own version to your instrument depends entirely on your imagination!

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Step 1: The Motor

Take off the plastic backing on the motor, the inside will look a bit like this, with the magnets around the edge and the coils around an axle in the middle.

Step 2: Small Holes

Drill a small hole inbetween the coils just about big enough to not destroy the magnets like what I did on my first attempt. Do the same on the back so that the string can travel all the way through...

its a good idea to glue the axle so that it doesn't spin.

Step 3: Small Solderings

Wire up the + and - terminals of the motor to a socket...

it doesn't matter which wire goes where.

Step 4: Ta Daa!

That's it!

The nitty gritty of why this works is pretty simple: electric pickups on guitars are just magnets and coiled wire, the vibrations of the strings create a fluctuation in the magnetic field which creates a very small alternating current in the wire. This is then sent off to an amplifier which comes out as noise. It's all called Faraday's law of Induction which is about one of the only things I remember from physics lessons. Electric motors work using the same Law of induction, so they're built from magnets and coils just like a pickup, the only difference is how they're utilised in everyday use, innit.

The 'instrument' in the demonstration below was a simple one-stringed instrument with a tuning peg at one end and an anchor at the other (for ideas on homemade/DIY tuning pegs, check out my post on it at my blog here.

I used two small L-Brackets in order to get the wire to the right height to pass through the motor without it touching the sides.

I've included an image of the pickup in-use in an instrument I built. The axle on the motor was at a different angle that allowed 2 strings to go through it.

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41 Discussions

(OUT OF THIS TOPIC)i have attached an led to a small toy motor .i want the motor rotate along with led glow..when i provide supply of 1.5 v .the led blinks several times (wont say dimm but same as bright when connected individually) but never glows constant..i guess led needs another normal diode or something ...plz help

It works! Thank you dude, great instructable and simple to follow. I used this and a few other instructables for my weekend project:

I fixed it! The solution: the brushes were bent out of shape (the metal contacts that connect the motor to the terminals). I actually had another motor and replaced the backing. Works great now! I just need to tune it...

Hurrah! Well done! I was going to ask if the wire was definitely conductive, and if so try adding stronger magnets to increase the sensitivity. Glad you got it going. Would love to see the results!

I'm trying to troubleshoot this, not sure if the wire is a bad choice, or if there's something wrong with the motor. The wire for the string is florist's wire (the green stuff, 24 gauge). The motor is just a normal 9v motor like the one you used. I noticed the motor wire is uninsulated, not sure if that would mess it up. I have it hooked to a preamp made from a cassette player (I need to link to the instructable I based it on), then to a computer speaker, so I am able to determine that my connections are good because I get pops and noise if I touch any bare metal from the preamp up to the motor terminals. And if I move the guitar string around so it touches the inside of the motor guts, I get a little noise. Something is going on but I cant get any induction.

I'm curious about making a pickup with more than one string. Would you use multiple motors, and wire them all together? Like 3 motor pickups with 2 strings in each, the three red wires soldered to one terminal of the socket, three black wires soldered to the other terminal?

I've not had time to play around with multiple motors yet, although I do intend to.

I would imagine it would be better to wire the motors up in series rather than in parallel (like how you suggested) to create one continuous loop.

I could be wrong! The best thing to do (as always) is experiment!

That one-string musical instrument is called a 'Diddly Bow." There are a few of them around but I never saw one with an electric motor for a pickup before. :)

Fantastic! :)
If this won't interest kids on Science, nothing will...
I daresay, this is Mindsets material, talk to them:
www.mindsetsonline.co.uk

Went to my Blog:
http://faz-voce-mesmo.blogspot.pt/2013/07/fablab-lisboa-concerteza-moldar-chapa.html

Oh that's what you meant by 'pickup!' I saw it out of context and couldn't figure out how you got from point A to point B.
excellent instructable!

3 replies

I too wondered what a 'pick up' was. I suppose if you are musically inclined you know straight away :) It would be like me saying I'll show you how to make a spinner. To some they'd think hub cap spinner on a car. Somebody else would think of some other sort of spinner while I would actually mean a fishing lure spinner :)

Anyway, to the 'ible'. Fantastic mate, well done. This is truly 'Instructable' thinking outside of the box to use something for another purpose than it was initially designed.

Remember the old "Norwegian 4 Bar Spinners" with a blue & white background.? It's a shame JC Whitney don't still carry them for restorers.