Instructables

Modify A Talking Skull To Say Anything You Want

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Every Halloween, inexpensive talking skulls are available as decorations. They look good, but they have a tiny speaker inside them, making them hard to understand. And they only say a few pre-programmed things. What if you could hack one so that you could make it say anything you want? And have it work with any speakers you own?

Here's what one that I got says. Notice that I have to snap my fingers at it to get it to play. Also, he doesn't just talk - he's got his own sound effects and music as well. I think this makes him harder to understand.



Some friends and I worked out how to do this inexpensively; as a matter of fact, this is the least expensive way possible to do this. These talking skulls are usually about $20.00 new, and less off-season. Other versions of this project on the web use parts that cost lots more than the skull!

Here's a quick explanation and demo:



We made a custom-designed circuit that needs less than $5.00 of parts – plus we’ve arranged with a company to offer a professionally printed circuit board so you can assemble it like a kit, instead of working out how to build it on prototyping board. And the cost of the circuit board is only $7.00, and less if you want more than one.

How it works: The circuit inside the skull is replaced by a small, custom-made board that will respond to “beeps” on an audio track; when the circuit hears a “beep” it turns on the motor in the skull, opening the mouth.
It’s a great project paired with a microcontroller (Arduino, EFX-Tek Prop-1, or Picaxe) that can trigger the playback of an MP3 or WAV file.

This is a multiple-part project, and you should have some experience in hobby electronics: Reading circuit schematics, soldering, assembling circuit boards, editing sound files on your computer, and programming a microcontroller to play back MP3s when you want.

2014 update: Someone asked if you could use this live with a microphone, so you could be hidden somewhere, and have a skull that is sitting on a table talk to people and react to what they say. Great idea! Yes, you can - there's a simple way (and it's easier than the original project!) Go to "Testing the skull" and see the notes at the bottom of the page.

 
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Jeff, have you ever run into an issue where continuity is confirmed to be working and responding to audio tones (using a multi-meter connected to motor out), and when I manually short the skull wires, the jaw moves down (and jaw springs closed), yet when I connect those same wires up to the motor output terminals, it doesn't work? It is as if the 4.5v from the skull is somehow feeding back into the circuit and messing it up. I suppose I could put a diode on the connection to confirm this, but it doesn't seem like I should have to based on your circuit. I have tried switching polarity around (on the skull battery box) without any luck either.

Also, I am using your custom designed PCBs.

Jeff Haas (author)  siliconghost29 days ago

No, I haven't seen that, but who knows how they modify the Gemmy skulls from year to year, as they add new features? The first thing I'd try is your idea about the diode - put that together with a breadboard and see what happens.

If you solve it, please let me know, there will be other people who could use the tip.

siliconghost11 months ago
Has anyone tried this with one of the Rite-Aid branded talking skulls? The design is a little different (LEDs for eyes) but I'm pretty sure it would work. http://www.halloweenforum.com/members/ghost-of-spookie-albums-halloween-store-items-2013-picture167837-riteaid-2013-animated-talking-skull-19-99.jpg
Jeff Haas (author)  siliconghost11 months ago
No one has mentioned that to me that they used one of those, but it looks like the same design with additional LEDs in the mouth. You'd have to buy one and see how it's wired up inside.
Thanks Jeff. I will reply back here on whether or not it works.

John
J4ckz1 year ago
awesome ...!

I am interested to make, if you have a PCB schematic of the circuit?
thx
Jeff Haas (author)  J4ckz1 year ago
Sorry, I don't have the PCB layout. I don't have the facilities to make my own PCB boards, which is why I went to SimpleCircuitBoards.com to have the board made. They did the board for me based on the schematic. Getting a copy of the board from them is fast and currently $7.00.

There's some stuff it's just easier to outsource.
I have tried to make it, but I wear menggapa motor can not move (dc motors), but his voice could come out of the speakers. What is the cause of my failure?
Please help me...

thx
Jeff Haas (author)  J4ckz1 year ago
Make sure to test each of the components - I show you how to test each component in the videos. See Step 6, and test the skull on its own, by shorting the two control wires together. And also see Step 8, to use your multitester to test the output from the circuit, so you can see that it closes the connection properly.

Also make sure you've got the connections to the battery box right - look at Step 5. If the testing of the skull and the circuit work OK, try swapping the connections to the battery box, they might have changed the way it's hooked up in yours. Use wires with alligator clips to try out all the different possibilities.

Good luck! This is an advanced project, just stick with it and you'll figure out what needs to be done to make your build work.
In the experiment you use dc motors with how much voltage volts?
Why dc motor that I use only rotates clockwise only?
Jeff Haas (author)  J4ckz1 year ago
The skull I have uses three AA batteries, for a total of 4.5 volts. The way they designed the jaw mechanism, it doesn't matter which way the motor turns - it winds up the string either way, to close the jaw, and then when the power to the motor is cut, the spring pulls the back open and unwinds the string.

As long as you can make your skull's jaw open and close when you close the connection, this circuit should work, because that's what the mosfet is doing - acting like a switch.
In addition to the above video if you still have that record video when motion of the motor circuit is working?

thx
Jeff Haas (author)  J4ckz1 year ago
All the videos I took of this project are posted. In steps 3 and 4 you can see how the hobby motor is hooked up. It pulls a lever connected to the jaw forward, opening the jaw.
LoopyMind1 year ago
To you Guybrush, +100 kudos for the Monkey Island skull sample on the mp3 player! :D
Jeff Haas (author)  LoopyMind1 year ago
:)
Btw jeff, are you of Dutch decent? :) ,wish a skull like that was sold here... halloween still hasn't really caught on here... in our neighborhood, my wife and I are always the ones organizing it... 5th year now. In all honesty, I think I enjoy it more then the kids :D
Jeff Haas (author)  LoopyMind1 year ago
Sorry, I'm not Dutch.

If you want to make a talking skull, your other option is to find a skull with a jaw that can move, and then use a servo to animate it. There's a schematic for a more complicated circuit that will drive the servo on Scary Terry's page (he's the guy who really kicked this whole idea off). http://www.scary-terry.com/
thnx for the link! here's one for you ;)
http://scummbar.com//resources/downloads/sounds/CMI-Murray3.zip
Cworkshop1 year ago
great work
Jeff Haas (author)  Cworkshop1 year ago
Thanks!
64001 year ago
cool

it is used as a driving force, dc motors or servo?
thank you
Jeff Haas (author)  64001 year ago
The board uses the existing motor in the skull and turns it on/off based on audio input from one stereo track of an mp3. It replaces the factory circuit board. Props of this type use inexpensive hobby motors so they can sell for $19.99.
magna65man1 year ago
is there any certain kind of microcontroller that you would suggest?
Jeff Haas (author)  magna65man1 year ago
Whatever you're comfortable programming...Arduino, Basic Stamp, etc. You'll want to be able to program it and also pick one of the many options for boards that play back MP3s. Since the skull is on its own circuit, you can use whatever you've got.
Panther1 year ago
I saw those same ravens at big lots recently.. Did you ever get around to hooking them up to this circuit? If so - how well did ti work. They have what appears to be, more points of articulation.
Jeff Haas (author)  Panther1 year ago
I haven't been able to get one of those ravens myself, but others I've talked to have. The way they work is that there's a motor that runs and the raven cycles through all its motions; if you were to turn the motor on and leave it on, you'd see the raven do everything it does over and over...flap its wings, open its beak, move side-to-side, whatever. If you watch this YouTube video of two of them you can see the movement clearly:
http://www.youtube.com/watch?v=Skx0v6i4Nvc

So you should be able to hook up the raven the same way as the skull (but without the blinking eyes). I'd suggest you put the raven up high, looking down at people, and use it with a microcontroller that turns an LED light on to spotlight it while it talks. Have the raven say very short things, and have it animate in quick bursts in sync with the words: "Squawk! Squawk! Beware! Beware! Squawk!" Record a handful of short phrases like this and cycle through them. And see which one of your friends does the best creepy raven voice. :)
Awesome! Thank you for the reply.. Looks like I am ordering some parts soon!
Kdemon1 year ago
I like this project, reminds me of Bob from the Dresden Files (book series)
jmomber1 year ago
Really bro couldn't show me this at Rosie's one of those days
Jeff Haas (author)  jmomber1 year ago
Sorry, I'm not sure who you are. Your profile show you're in Texas, I'm in California.